Recording apparatus, computer-readable program, and system lsi

ABSTRACT

Provided is a recording apparatus that prompts a user to judge whether non-referenced part in a DVD should be deleted or not, thereby facilitating cleanup of recorded contents in the DVD. A playlist editing unit ( 15 ) obtains a PL by performing a playlist editing, where the playlist is a logical playback path defined on a VOB recorded in the DVD and contains at least one playback section defined by the user. After the playlist editing is performed, a non-referenced part extraction unit ( 17 ) displays to the user a plurality of remaining parts resulting after subtracting from the entire VOB the playback section specified by PL information, as a plurality of non-referenced parts in a moving image stream. A substantial editing unit (18) deletes any of the displayed non-referenced parts, according to a user operation.

TECHNICAL FIELD

The present invention relates to a recording apparatus such as a DVDrecorder, a computer-readable program, and a system LSI, that are forrecording moving image streams in a recording medium to which randomaccess is allowed. The present invention particularly relates toimprovement in performing editing processes relating to the moving imagestreams recorded in a recording medium.

BACKGROUND ART

Each manufacturer, in expectation of users' demand for DVD recorders toreplace their VTRs, started to introduce recording apparatuses equippedwith various additional functions. A representative example of suchadditional functions is editing functions directed to playlist.

The playlist (PL) is a logical playback path defined for a moving imagestream recorded in a DVD, and includes one or more playback sectionsdefined by a user.

The conventional playlist editing for a playlist having the mentionedstructure is composed of: a process of defining playback sections to beincluded in a playlist; and an order-assigning process for the playbacksections.

In the process of defining playback sections, a GUI for receivingediting operation for a moving image stream is displayed, so as toreceive, from a user, specification as to from which point the userwants to start playback of the moving image stream (playback startingpoint), and which point the user wants to end the playback (playbackending point). Once the user defines these playback starting/endingpoints, the pointer information indicating the defined playbackstarting/ending points is written to a DVD. This pointer information isthe playback section information for specifying the playback sections,and the defining process for the playback sections will end withcompletion of writing this playback section information.

If two or more playback sections are defined in the process of definingplayback sections, then the operation for assigning order to theplayback sections is received from the user, the order specificallybeing the playback order in which the playback sections are to be playedback. A playback path is defined, by arranging pieces of playbacksection information that each define a playback section according to thedesired playback order.

The DVD prestores a plurality of pieces of playlist information, eachshowing a playback path. Then, the recording apparatus is able to notonly play back the moving image stream that is in the DVD, in the orderas it is, but also play back according to any playback paths shown bythe pieces of playlist information. The playlist editing enablesincrease in variation of playback with facility.

One example of the prior arts realizing such playlist editing is listedbelow as “patent reference 1”.

<Patent Reference 1>

U.S. Pat. No. 6,181,870

Incidentally, after such playlist editing has been repeated, thefree-area of the DVD will inevitably decrease, because non-referencedpart not used by the playlist will remain in the DVD. The non-referencedpart is specifically a remainder after the playback sectionsconstituting the playlist are subtracted from the entire moving imagestream. Because the data of the non-referenced part will remainundeleted, another recording is sometimes refused in a DVD.Theoretically, if playback according to the playlist is more and morefrequent, with fewer playbacks according to the original moving imagestream as it is, all the non-referenced parts should be deleted.However, such a drastic deletion directed to non-referenced partssometimes causes the user to regret another day, when he realizes theworth of the images in the deleted parts. The user therefore dithers andprocrastinates deletion of the non-referenced parts, thinking thatsomeday he might need the parts. This is one cause of lack in free area.

Furthermore, in a case when a plurality of playback paths are definedthat have overlapping parts with each other, it is even difficult tounderstand which part is a non-referenced part, causing the user to beunwilling to organize the contents recorded in the DVD.

DISCLOSURE OF THE INVENTION

In view of the above-described problem, the object of the presentinvention is to provide a recording apparatus that prompts a user tojudge whether non-referenced part in a recording medium should bedeleted or not, thereby facilitating cleanup of recorded contents in therecording medium.

This object is achieved by a recording apparatus that writes a videostream to a recording medium and edits the video stream, the recordingapparatus including: an editing unit operable to specify, in accordancewith a user operation, a plurality of parts of the video stream asplayback sections; a display unit operable to display to the user, aplurality of parts that remain after the playback sections aresubtracted from the video stream, as non-referenced parts; and adeletion unit operable to delete at least one of the displayednon-referenced parts from the recording medium, according to a useroperation.

When there is a small shortage in free area for recording a new content,enough free area is allocated by deleting some of a plurality ofnon-referenced parts having been extracted. Accordingly, it preventslosing of an opportunity of recording another broadcast content. Indeletion, a plurality of non-referenced parts are displayed to the user,among which the user can choose parts to be deleted. With thisconstruction, it becomes possible to choose some whose preservationvalue is relatively low from among the displayed non-referenced parts,thereby enabling a new content to be recorded. By doing this, the userwill be prevented from regretting over lost contents' portions, and atthe same time, new recordings can be realized.

The applicant recognizes the distinguished effect of the presentinvention over the invention of the patent reference 1. The patentreference 1 discloses a technology for creating cell information in apreparatory process called “virtual editing”, and for performingbatch-deletion on images that are out of range specified by the cellinformation. However the batch-deletion might cause the user to regret,because all the images including those worthy of preservation will bedeleted at once. As opposed to this, the present invention offers theuser an opportunity of confirming the deletion, by displaying thecontents of the non-referenced parts. This enables individual deletionin which only unnecessary non-referenced parts are deleted, whileretaining non-referenced parts including valuable images. Therefore, theuser will be prevented from regretting.

Here, each of the playback sections maybe represented by a set ofstarting/ending positions of a playback operation, and the plurality ofnon-referenced parts may include a part from a front-end of the videostream to immediately before a starting position of one of the playbacksections that appears first, and a part from immediately after an endingposition of one of the playback sections that appears last to a rear-endof the video stream. In a case where there is no playback section at thefront-end or at the rear-end of the video stream, this constructionenables extraction of the part from the front-end of the video stream toimmediately before the starting position of the first playback section,and the part from immediately after the ending position of the lastplayback section to the rear-end of the video stream, without performinginteractive operation with the user that relates to specification of thementioned non-referenced parts of the video stream. This enhances theconvenience for the user.

More specifically, once such playback sections are specified at aplaylist editing, the mentioned non-referenced parts will be identifiedautomatically by referring to this specification. According to this,only an operation of “playback section specification plus non-referenceparts selection” enables non-referenced part deletion. This greatlysaves time and trouble compared to the conventional procedure in whichstarting/ending points of each non-referenced part are specified via aninteractive operation with the user, the range of deletion is decided,and finally the deletion is performed. Therefore, the user will be moreencouraged to delete the non-referenced parts.

Here, the non-referenced parts may include every part immediately afterone of the playback sections to immediately before another of theplayback sections that follows. With this construction, every gap-partbetween one of the playback sections and another of the playbacksections that follows is also extracted automatically, as non-referencedpart. Therefore, this construction saves time and trouble necessary forinteractive operation relating to specification of such gap-parts,thereby enabling non-referenced parts to be extracted with facility.

Here, the display performed by the display unit may be one of:sequential playback of a plurality of pieces of picture data included inthe non-referenced parts; and disposing, on a screen, of a plurality ofthumbnails each corresponding to the pieces of picture data. With thisconstruction, judgment as to whether an image worthy of preservation isincluded in the non-referenced parts can be instantly performed, therebyaccelerating the cleanup of non-referenced parts.

Furthermore, it serves as impetus to prompt the user to decide thedeletion, to put the plurality of non-referenced parts existing in therecording medium in an actual display to the user, who has dithered andprocrastinated the deletion vacillating over thoughts that he might ormight not need these parts in the future.

Here, a plurality of video streams may be written to the recordingmedium, each stream being classified into two or more contents, and thedeletion unit deletes only non-referenced parts included in a certaincontent.

With this construction, in a case where two or more video streams areclassified into one content, the video streams belonging to that contentcan be collectively deleted. This greatly saves time and troublecompared to the case in which the non-referenced parts are deleted oneat a time.

Here, it is also possible that the recording apparatus further includesa reception unit operable to receive, from the user, an operation forprogramming a recording; and a calculation unit operable to calculate anarea size required for the programmed recording, where the display unitperforms the display, only if the calculated area size exceeds a freearea size of the recording medium, and the display unit further displaysa message making an inquiry to the user about whether the non-referencedparts should be deleted. With this construction, display ofnon-referenced parts will be performed when there is no free area forthe programmed recording. Since the user will be prompted to delete thenon-referenced parts if the user has noticed the need for free area atthe recording programming stage, the cleanup of non-referenced part isfacilitated. In addition, the need for abandoning the recordingprogramming can be circumvented.

Here, it is also possible that the recording apparatus further includesa reception unit operable to receive, from the user, specification of anenvironment setting value, the environment setting value being a minimumfree area size that the recording medium should allocate, where thedisplay unit performs the display, only if the calculated area sizeexceeds a free area size of the recording medium, and the display unitfurther displays a message making an inquiry to the user about whetherthe non-referenced parts should be deleted.

With this construction, the user is allowed to set in the recordingapparatus the length of broadcast content that the user plans to recordin the future. Since the operation of prompting the user to delete thenon-referenced parts will be only performed when the free area size ofthe recording medium falls short of this length, this would leave theuser enough time to prepare for the recording of the broadcast content.

Here, it is also possible that the recording apparatus further includesa backup unit operable to record therein a backup of the non-referencedparts, prior to the deletion performed by the deletion unit; an inquiryunit operable, after the deletion performed by the deletion unit, tomake an inquiry to the user about whether an undo operation should beperformed; and a write back unit operable, if the user's answer to theinquiry is affirmative, to write back the backup recorded in the backupunit to the recording medium.

With this construction, if the user notices the value of the alreadydeleted non-referenced part, the part can be written back to therecording medium, preventing the user to regret over the lost part. Inaddition, the parts to be recorded as a backup are narrowed to only thepart actually deleted. This circumvents increase of memory areasoccupied by backups. More specifically, in the real editing described inthe patent reference 1 where the batch deletion of a plurality ofnon-referenced parts is performed, all the non-referenced parts arerequired to be retained, thereby leading to a great increase in thememory capacity for non-referenced part backup. However, with theplayback apparatus according to the present invention, what is needed isa memory capacity sufficient for recording one non-referenced part,thereby preventing enormous increase in memory size of the playbackapparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing the contents recorded in the DVD.

FIG. 2 is a diagram showing a PG comprised of a VOB, and one or morepieces of management information regarding the VOB.

FIG. 3 is a diagram showing one example of the PL information created inthe playlist editing.

FIG. 4 is a diagram showing, in a case where the PL information shown inFIG. 3 is generated, which part of the VOB sequence can benon-referenced part.

FIG. 5 is a diagram showing the outer appearances of the recordingapparatus and the DVD, relating to the present invention.

FIG. 6 is a diagram showing one example of the route menu.

FIG. 7 is a diagram showing one example of the playlist-editing menu.

FIG. 8 is a diagram showing one example of the PG playback menu.

FIG. 9 is a diagram showing one example of the PL playback menu.

FIG. 10 is a diagram showing one example of the substantial editingmenu.

FIG. 11 is a diagram showing the internal structure of the recordingapparatus.

FIG. 12 is a diagram showing the main routine performed by theapplication unit 14.

FIG. 13 is a flowchart showing the procedures performed by the playlistediting unit 15.

FIG. 14 is a flowchart showing the procedures performed by thesubstantial editing unit 18.

FIG. 15A is a diagram showing a case in which the beginning part of theVOB sequence is specified as a cell of any PL.

FIG. 15B is a diagram showing a case in which the beginning part of theVOB sequence is not specified as a cell of any PL.

FIG. 16 is a diagram showing how the repetition of this loop operationspecifies non-referenced parts.

FIG. 17A is a diagram showing one example of the case in which theOut-point of the Cell#x coincides with the rear-end of the VOB sequence.

FIG. 17B is a diagram showing one example of the case in which theIn-point of the Cell#x coincides with the front-end of the VOB sequence.

FIGS. 18A and 18B are diagrams respectively showing a case in whichSteps S38-S44 are repeated.

FIGS. 19A and 19B are diagrams respectively showing a case in whichSteps S38-S44 are repeated.

FIG. 20 is a diagram showing a case in which two PLs, namely PL#1 andPL#2 are defined on a VOB sequence.

FIG. 21 is a flowchart showing the procedure performed by thesubstantial editing unit 18.

FIG. 22 is a flowchart showing the procedure for the batch deletion ofthe non-referenced parts in the DVD.

FIG. 23 is a diagram showing the PG navigator relating to the secondembodiment.

FIG. 24 is a flowchart showing the PG playback relating to the secondembodiment.

FIG. 25 is a diagram showing one example of the PG navigator relating tothe third embodiment.

FIG. 26 is a flowchart showing the playback process regarding the PGnavigator assigned a check box.

FIG. 27 is a diagram showing one example of the picture recordingprogramming menu.

FIG. 28 is a flowchart showing the procedure of the picture recordingprogramming performed according to the menu of FIG. 27.

FIG. 29 is a diagram showing one example of the menu for receivingenvironment setting.

FIG. 30 is a flowchart showing the main flowchart structured to performoperations according to the environment setting.

FIG. 31 is a flowchart for receiving the operation via the environmentsettings menu.

FIG. 32 is a flowchart showing the procedure of returning thenon-referenced part back to the PlayList.

FIG. 33 is a diagram showing the process in which the non-referencedpart #r to be returned to the PlayList is specified.

FIG. 34 is a diagram showing the process in which the non-referencedpart #r to be returned to the PlayList is inserted between the cellinformation #p and the cell information #p+1.

FIG. 35 shows the data structure of a moving image stream to be recordedin a BD-RE, under the same notation system as used in FIG. 3.

FIG. 36 is a diagram showing the non-referenced part of the moving imagestream of FIG. 35.

FIG. 37 is a diagram showing a Bridge part.

FIG. 38 is a diagram showing another Bridge part.

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment

The following explains an embodiment of a recording apparatus thatrelates to the present invention. Before explaining the recordingapparatus of the present invention, an object of editing by therecording apparatus is explained. The object of editing by the recordingapparatus is, in other words, a content recorded in a DVD. The contentis comprised of one or more VOB (Video Object) s, and managementinformation for each of the VOBs. Such a content is called a PG(ProGram) in the field of DVD. The VOBs and corresponding managementinformation are recorded in a DVD, in accordance with the data structureshown in FIG. 1. FIG. 1 is a diagram showing a content recorded in aDVD. A DVD 100 stores therein a VOB sequence and a managementinformation sequence, as shown by a broken line hs0 in FIG. 1.

The VOB sequence is comprised of a plurality of VOBs (VOB#1, VOB#2, andVOB#3), as shown by a broken line hs1.

The VOB is a moving image stream which is in the MPEG-PS (ProgramStream) format, obtained as a result of interleave multiplexingperformed in relation to a video stream and an audio stream. The videostream is a plurality of pieces of picture data having been subjected tocompression encoding. Each piece of picture data corresponds to oneimage, and is displayed in a display period of image signal, which isabout 33 m seconds. The audio stream is composed of a plurality of audioframes having been subjected to compression encoding.

The VOB obtained by the interleave multiplexing has a structure in whicha plurality of VOBUs are arranged chronologically, as shown by thebroken arrow line hs2. The VOBU (Video Object Unit) is a minimumdecodable unit of VOB, and includes a GOP and a plurality of audioframes to be concurrently played back with this GOP, the GOP being acollection of pieces of picture data each corresponding to 0.4-1.0second. Playback can be performed from any point if it is the beginningof a VOBU, meaning that the VOB can be randomly accessed, at such ashort time interval as 0.4-1.0 second.

Next, the management information sequence is described. The managementinformation sequence is, as shown by the broken arrow line hs3,comprised of a plurality of pieces of management information (i.e.management information #1, #2, and #3) each corresponding to the VOB#1,VOB#2, and VOB#3. Each piece of management information is composed of“time map” and “cell information”, as shown by the broken arrow linehs4.

“Time map” is a reference table used in making indirect reference to theaddress of each random-accessible position in a VOB, with use of timeinformation. The “Time map” is comprised of pieces of entry information(VOBU#1 entry information, VOBU#2 entry information, VOBU#3 entryinformation . . . ) each corresponding to a VOBU. In each piece of entryinformation, “VOBU playback time” showing the time required for playbackof the particular VOBU, is corresponded to “VOBU size” showing the sizeof data for the VOBU. Because of adoption of the variable-lengthcompression encoding method, it is possible to perform random accessfrom an arbitrary playback time to the picture data within the VOBU thatcorresponds to the particular playback time, even when the size and theplayback time of each VOBU including a GOP, vary.

Cell information is pointer information that defines one or more logicalplayback sections that constitute a PG. The cell information ischaracterized by the notation system used. In this notation system, aplayback section is defined using the time map as a reference table asindirect reference. The reason why cell information is described inindirect reference notation is for eliminating a burden of updating thecell information, incident to editing performed in relation to the VOB.As shown by the leader line hs6, cell information is comprised of:“VOB-ID” of VOB to which the In-point and the Out-point of the VOBbelong to; “Cell_Start_PTM” representing a relative time from thefront-end of the VOB to the In-point; and “Cell_End_PTM” representing arelative time from the front-end of the VOB to the Out-point. Each VOBUhas 0.4-1.0 second time accuracy, whereas these “Cell_StarT_PTM” and“Cell_End_PTM” have 33 m-second time accuracy, which is less than thedisplay period of one image. Accordingly, In-point/Out-point of a cellare represented by a time accuracy used for each piece of picture databelonging to a VOBU.

FIG. 2 shows PGs each being comprised of a VOB and managementinformation for the VOB. This diagram describes a VOB sequence comprisedof three VOBs, VOB#1, VOB#2, and VOB#3, and in addition, describes threetime maps #1, #2, and #3, and three pieces of cell information #1, #2,and #3. In this diagram, the set of “VOB#1-time map#1-cell information#1” constitutes the first PG (PG#1). Likewise, “VOB#2-time map#2-cellinformation #2” constitutes the second PG (PG#2); and “VOB#3-timemap#3-cell information #3” constitutes the third PG (PG#3). In otherwords, a set of “VOB-time map-cell information” constitutes one PG.

In the described DVD, “playlist (PL) editing” is defined as follows.That is, after receiving from a user a position-deciding operation fordeciding In-point/Out-point, the recording apparatus generates a newpiece of cell information (1), and generates data called PL information,after reception of an operation for assigning playback order to eachpiece of cell information (2). The PL information is substantialinformation that defines a playlist.

The following describes one example of PL information obtained by theplaylist editing. FIG. 3 is a diagram showing one example of PLinformation created by the playlist editing. The playback path definedby the PL information #2 orders to playback a part (1) of VOB#1, a part(2) of VOB#2, and a part (3) of VOB#3, in the order of (1), (2), and(3). The playback path defined by the playlist #1 orders to playback apart (4) of VOB#1, and a part (5) of VOB#2, in the order of (4) and (5).The PL information#1 includes the cell information #1, #2, and the PLinformation #2 includes the cell information #1, #2, and #3,respectively. These pieces of cell information specify starting/endingpoints from the part (1) to the part (5), by indirect reference via thetime maps. Since specified by cell information, the parts (1)-(5) willbe treated as cells.

In this drawing, the arrow signs rf1, rf2, rf3, rf4, rf5, and rf6symbolically show this indirect reference. As understandable from thearrow signs rf1, and rf2, the starting points st1, st2, and st3, and theending points ed1, ed2, and ed3, for the parts (1)-(5) of VOBs #1, #2,and #3, are specified by indirect reference via the respective timemaps.

In the PL editing, a remaining part (referred to as “non-referencedpart”) is sometimes generated in the VOB sequence. The non-referencedpart is a part not referenced by any cell information constituting anyPLs, and has much possibility of being deleted. The recording apparatus,after performing the PL editing, extracts non-referenced parts, todisplay the extracted non-referenced parts to the user, therebyprompting the deletion of the displayed parts. After that, in accordancewith the user operation, the recording apparatus performs the deletion.The editing process in which non-referenced parts are deleted is called“substantial editing”.

Please note that the deletion of a non-referenced part mentioned aboveis to release an area of a DVD to a free area, the area of a DVDcorresponding to where the non-referenced area of the VOB sequence isstored. Such release into a free area is performed by updating of thefile entry in the file system of the DVD. As follows, the release intofree area is described in detail. In a DVD, a VOB sequence is recordedin the state stored in a file. Just as for normal files, the file entryof the file system manages where in the DVD each VOB of the VOB sequenceis recorded and how long the VOB is. By being managed by this fileentry, the VOB sequence can be fragmented just as the normal files.Since the addresses of the VOBs are managed by the file entry, if thefile entry is updated to indicate that among the occupied area by theVOB sequence, the part of the area corresponding to the non-referencedpart should be skipped, then the part of the DVD will be released to afree area. This is what the deletion of non-referenced part means.

When the example of PL information described in FIG. 3 is generated,which part of the VOB sequence can be non-referenced part is shown inFIG. 4. As shown in FIG. 4, in the example of FIG. 3, from the front-endof the VOB sequence to immediately before the part (1) is the firstnon-referenced part (non-referenced part #1), from immediately after thepart (4) to immediately before the part (2) is the second non-referencedpart (non-referenced part #2), from immediately after the part (5) toimmediately before the part (3) is the third non-referenced part(non-referenced part #3), and from immediately after the part (3) to therear-end of the VOB sequence is the fourth non-referenced part(non-referenced part #4). The recording apparatus relating to thepresent invention performs deletion of such non-referenced parts.

Next, among the embodiments of the recording apparatus of the presentinvention, the embodiment relating to usage of the recording apparatusis described. The recording apparatus relating to the present invention,together with a television and a remote controller, makes up a hometheater system, and is provided for use of the user together with suchtelevision and remote controller. The usage by the user means that theuser performs a PL editing and a substantial editing, in collaborationwith a television 101 and a remote controller 102.

FIG. 5 is a diagram showing the outer appearance of the recordingapparatus and a DVD, relating to the present invention. As shown in thisdrawing, the recording apparatus is connected to the television 101, andis operated through the remote controller 102, for playing back the DVD100.

The television 101 displays a GUI (graphical user interface) made up ofhierarchical menus, and playback images for PL and PG.

The remote controller 102 is an apparatus that receives from a user anoperation directed to the hierarchical GUI. For receiving such anoperation, the remote controller 102 is equipped with a menu key forinvoking menus constituting the GUI, an arrow key for changing the stateof the GUI parts constituting a menu, a deciding key for performing thedeciding operation in relation to the GUI parts constituting a menu, anda return key for returning to the higher order menu in the hierarchy.

The GUI displayed in this television 101 is described. In the television101, the GUI is drawn by the OSD (On Screen Display) data. The OSD datais simplified graphics drawn with use of 2, 4 colors shown in Look UpTable (LUT) as background color, and character color. Whereas the VOBand management information constituting a PG are prestored in the DVD,this OSD is generated by the recording apparatus in case of necessity,and is freely updated in accordance with a user operation. The recordingapparatus draws the GUI necessary for playlist editing and substantialediting, with use of the OSD, and realizes interactive operation byfreely updating the OSD.

The GUI used in interactive operation performed by the recordingapparatus is shown in FIG. 6-FIG. 10. The GUI used in interactiveoperation is made up of hierarchical menus as shown in FIG. 6. In FIG.6, the route menu mn1 is situated at the highest order in thishierarchical structure. When the user pushes the menu key in the remotecontroller, the route menu mn1 will be displayed. This route menu is forreceiving a user selection among the items “PG playback”, “playlistplayback”, “playlist editing”, “substantial editing”, and so on.

Furthermore, under this route menu, lower order menus such as “PGplayback menu”, “PL playback menu”, “PL editing menu”, and “substantialediting menu”, and so on.

The arrow signs in the drawing schematically show the switching from onemenu to another. If the “playlist editing” in the route menu isselected, switching is performed from the route menu to the PL editingmenu, as shown by the arrow sign yc1. If the item “PL playback” in theroute menu is selected, switching is performed from the route menu tothe PL playback menu, as shown by the arrow sign yc2. If the item “PGplayback” in the route menu is selected, switching is performed from theroute menu to the PG playback menu, as shown by the arrow sign yc3, andif the item “substantial editing” in the route menu is selected,switching is performed from the route menu to the substantial editingmenu.

As follows, the menu used in playlist editing is described. FIG. 7 showsan example of the menu used in playlist editing.

The playlist editing menu is made up of such GUI parts as a slide barwd1, a window wd2, an In-point/Out-point buttons wd3 and wd4, a cellnavigator wd5, and numerical value fields wd6, wd7, and wd8.

The slide bar wd1 is a GUI part for receiving from a user aposition-deciding operation to decide the In-point/Out-point for a cell.By pushing the left/right key of the remote controller 102, the slidebar can be moved on the guide in left and right directions, and theposition-deciding operation is performed by converting the position ofthe slide bar on the guide, into the position on the VOB. For example ifthe object of playlist editing is two-hour VOB, and the slide barpositions substantially in the middle of the guide, then the positionafter one hour from the front-end of the VOB will be specified.

The window wd2 is a GUI part for giving user a feedback on which part ofthe VOB has been specified by the position-deciding operation for theslide bar. According to the position-deciding operation in relation tothe slide bar, and the feedback by means of the window wd2, fineadjusting of the positions to be In-point/Out-point is realized.

The In-point/Out-point buttons wd3 and wd4 are GUI parts for finallydeciding the positions of the slide bar in the guide, asIn-point/Out-point. Once the In-point and the Out-point for a cell aredecided, by pushing of the In-point/Out-point buttons, this results ingeneration of the cell.

The cell navigator wd5 graphically represents the cell generated by theposition deciding by means of the slide bar and of the decidingoperation in relation to the In-point/Out-point. Specifically, the cellis represented by a thumbnail for the picture data positioning at theIn-point of the cell (playback section), and a thumbnail for the picturedata positioning at the Out-point of the cell. If the two or more cellsare already generated, then the cell navigators will appear in thescreen, in the same number as for the generated cells (three cellnavigators in FIG. 7 imply that the three cells are already generated).The PL is comprised of cells represented by these cell navigators.

The numerical value fields wd6, wd7, and wd8 are for receivingorder-assigning operation for each cell navigators. This order-assigningoperation is performed by input in the numerical value field a numericalvalue from among 1−n. “n” represents a total number of cells,represented by the cell navigators. The numerical value inputted in thisnumerical value field is interpreted as a playback order of thecorresponding cell.

Generating process of a PL is as follows: the cells are defined by theposition-deciding operation by means of the slide bar and by thedeciding operation in relation to the In-point/Out-point buttons; then,the playback order of each cell is defined by means of input of anumerical value in the numerical value field of each cell navigator.

Next, the menu that the recording apparatus uses in PG playback isdescribed, with reference to FIG. 8. FIG. 8 is a diagram showing themenu that the recording apparatus uses in PG playback. In the menu ofFIG. 8, three PG navigators are disposed. A PG navigator is a GUI partthat graphically describes a PG. In the PG navigator, the following aredisposed: recording date/time “gv1” of the PG (made up of the date ofrecording and the time of recording); a broadcast channel “gv2” throughwhich the PG was broadcasted; the title of the PG“gv3”; and thumbnails“gv4” and “gv5”, respectively for the front-end/rear-end images of thePG. The PG navigator has three states: normal state; focus state; andactive state. The normal state is a state of not being selected by auser; the focus state is a state of being selected as a playbackalternative by means of the arrow key of the remote controller; and theactive state is a state of being decided as the program to be playedback. By changing the state of each PG navigator, it is possible toeasily perform selection as to “which PG has to be played back”.

Following this, the menu to be used in PL playback is described withreference to FIG. 9. FIG. 9 is a diagram showing the menu that therecording apparatus uses in PL playback. The menu in FIG. 9 has two PLnavigators. In each PL navigator, cell navigators “cv1”, “cv2”, “cv3”,that constitute the PL are disposed in accordance with the cells'playback order. Also included in each PL navigator are the date/time ofediting “nt1” and the title “nt2”.

The PL navigator, just as the PG navigator, has three states: normalstate; focus state; and active state. The normal state is a state of notbeing selected by a user; the focus state is a state of being selectedas a playback alternative by means of the arrow key of the remotecontroller; and the active state is a state of being decided as theprogram to be played back. The recording apparatus plays back the PLthat corresponds to the PL navigator that has been set to the activestate in this PL playback menu.

Next, the substantial editing menu is described with reference to FIG.10. FIG. 10 is a diagram showing one example of the substantial editingmenu. The substantial editing menu includes therein: a plurality ofnon-referenced part navigators “uv1”, “uv2”, and “uv3”, and a batchdeletion button “un5”. Each non-referenced part navigator is a GUI partfor graphically representing a non-referenced part. An identifierrelating to the non-referenced part, and two thumbnails “ut2” and “ut3”represent each non-referenced part navigator. The two thumbnails, in anon-referenced part navigator, each are reduced images obtained byscaling down pieces of picture data each belonging to thefront-end/rear-end of the non-referenced part. By looking at thethumbnails included in each non-referenced part navigator, the user cansurmise whether the non-referenced part contains a valuable image worthyof preservation or not.

The non-referenced part navigator has three states: normal state; focusstate; and active state. The normal state is a state of not beingselected by a user; the focus state is a state of being selected as adeletion alternative by means of the arrow key of the remote controller;and the active state is a state of being decided as the part to bedeleted. The recording apparatus displays non-referenced part navigatorsin response to the user's choosing of a substantial editing. Therefore,at the time when a user shows intention of performing substantialediting, the user can know how many parts can be deleted.

The batch deletion button un5 is a GUI part to be assigned to such as apicture-recording key of the remote controller, and receives anoperation that all the non-referenced parts displayed in the menu shouldbe deleted collectively.

The usage of the recording apparatus relating to the present inventionis to make the recording apparatus perform playlist editing, substantialediting, and playback operations, with use of the aforementioned GUI.

Next, among the various embodiments that the recording apparatus of thepresent invention has, the embodiment relating to the production of therecording apparatus is described. The recording apparatus relating tothe present invention is mainly made up of two parts: a system LSI, anda drive device, and is industrially manufacturable by mounting theseparts to the cabinet or to the board, of an apparatus. The system LSI isa circuit into which varieties of process units performing functions ofthe recording apparatus are integrated. FIG. 11 is a diagram showing theinternal structure of the recording apparatus. As shown in this drawing,the recording apparatus is made up of a DVD drive 1 and a system LSI.The system LSI is comprised of hardware resources such as: a DVD drive1, a tuner 2, an MPEG encoder 3, an MPEG decoder 4 (including a systemdecoder 5, an audio decoder 6, and a video decoder 7), frame memories 8a, b, c, an order controlling unit 9, an OSD generator 10, a signalsynthesizing unit 11, and a micro computer system 12. These constitutingelements are described as follows.

The DVD drive 1 is an apparatus to which the DVD 100 is loaded. The DVDdrive 1 reads an arbitrary VOBU from the DVD, and deletes an arbitraryVOBU from a DVD. The reading/deletion of VOBUs are performed accordingto read commands and delete commands that the system LSI issues.

The tuner 2 demodulates a broadcast signal for television, therebyoutputting an image signal and an audio signal to the MPEG encoder 3.

The MPEG encoder 3 obtains a VOBU by encoding image/audio signals thathave been demodulated by the tuner 2. In addition, the MPEG encoder 3performs re-encoding, where the already encoded two VOBUs are encodedagain to synthesize them to one VOBU.

The MPEG decoder 4 is a dedicated circuit for decoding the VOBU read bythe DVD drive 1, and is equipped with the system decoder 5, the audiodecoder 6, and the video decoder 7.

The system decoder 5 obtains a GOP and a plurality of audio frames, bymaking the video decoder 7 perform multiplex separation on a VOBU.

The audio decoder 6 decodes the plurality of audio frames, therebyobtaining an audio signal.

The video decoder 7 performs, on a bidirectionally predictive (B)picture, predictive (P) picture, and an intra (I) picture, suchprocesses as VLD (variable-length code decoding), IQ (inversequantization), IDCT (inverse DCT conversion), and MC (motioncompensation), thereby storing picture data in a digital non-compressedstate in the frame memories 8 a, b, and c.

The frame memories 8 a, b, and c are respectively assigned to the threetypes of picture data (i.e. I picture, B picture, and P picture).Accordingly, each frame memory 8 a, b, and c separately stores picturedata in non-compressed state, which have been obtained by decompressingthe three types of picture data.

The order controlling unit 9 sequentially reads pieces of picture data,in the non-compressed state, stored in the frame memories 8 a, b, and c,at a timing shown by the PTS (presentation time stamp) assigned to therespective pieces of picture data. On the other hand, theorder-controlling unit 9 sequentially outputs the PTSs themselvesassigned to the respective pieces of picture data, to the microcomputersystem 12. While being stored in the DVD 100, the plurality of pieces ofpicture data constituting a VOBU are aligned in an order called“encoding order”. In playback of the VOBU, the pieces of picture datamust be realigned in the display order. The order controlling unit 9, soas to perform such realigning, reads, according to the order shown inthe PTSs, the I picture, P picture, and B picture, that have beenrespectively stored in the frame memories 8 a, b, and c.

Since PTSs assigned to the corresponding piece of picture data areoutputted to the microcomputer system 12, the microcomputer system 12can know playback time to which each piece of the picture data stored inthe frame memories 8 a, b, and c, corresponds. Therefore, pieces ofpicture data are freely used, such as reading pieces of picture datafrom the frame memories 8 a, b, and c, and after reducing, disposingthem on the PL editing menu.

The OSD generator 10 generates the OSD representing the menu shown inFIG. 6-FIG. 10, and outputs the OSD to the signal-synthesizing unit 11,so that the OSD will be synthesized with picture data. Then the OSD isupdated according to a user operation performed on the remotecontroller. Updating of the OSD includes changing a PL navigator and aPG navigator to a focus state from a normal state, and moving the slidebar on the guide in left and right directions. Thanks to the OSDupdating performed by the OSD generator 10, operations are realized suchas a position-deciding operation for deciding the In-point/Out-point ofa cell, and an order-assigning operation for assigning the playbackorder to each cell.

The signal-synthesizing unit 11 synthesizes the OSD with picture data,by mixing the horizontal lines constituting the non-compressed picturedata and the horizontal lines of the OSD, thereby converting the picturedata into an image signal for television. According to the mixing ratioset in this mixing operation, the signal-synthesizing unit 11 can makethe picture data covered by the OSD, or make the picture data besee-through.

The microcomputer system 12 is equipped with a CPU 12 a, a RAM 12 b, andan instruction ROM 12 c, and performs integration/control by making theCPU 12 a execute the program stored in the instruction ROM 12 c. Theinstruction ROM 12 c prestores a basic program for realizing theconversion function between time-and-address, and an applicationprogram. These programs function as a time-address conversion unit 13and as an application unit 14, by being read by the CPU 12 a.

So far is the description on the hardware structure of the recordingapparatus. Next, the software structure of the recording apparatus isdescribed. The software structure of the recording apparatus iscomprised of the time-address conversion unit 13 and the applicationunit 14.

As follows, this software structure is described.

The time-address conversion unit 13 receives, from the application unit14, specification of a VOB-ID, and relative time for theIn-point/Out-point. These ID and relative time are then converted to thestart address of a VOBU. This conversion operation is performed withreference to the time map. More specifically, in the VOB identified bythe VOB-ID received by the application unit 14, calculation is performedas to the position of the VOBUs that respectively include theIn-point/Out point, from the beginning of the VOB in byte, withreference to the time map. By this operation the start address of theVOBU is calculated. Then, directed to this start address, a read commandand a delete command are issued in the DVD drive 1. By involving thetime-address conversion unit 13, the application unit 14 does not haveto think about the address of each VOBU in the DVD, in performing PLediting, substantial editing, and PG/PL playbacks.

The application unit 14 is the actual means realized by collaborationbetween the application program and the hardware of the microcomputersystem 12, and is equipped with a playlist editing unit 15, a playbackcontrol unit 16, a non-referenced part extraction unit 17, a substantialediting unit 18, and a virtual free-area calculation unit 19.

The PL editing unit 15 generates a PL, based on a position-decidingoperation of deciding the In-point/Out-point of cells, and anorder-assigning operation of assigning playback order to each cell, thatare performed in response to the display of playlist editing menu. Morespecifically, the playlist editing unit 15 acquires the VOB-ID of theVOB that the In-point belongs to, as well as acquiring the relative timefrom the front-end of the VOB to the In-point (Cell_StarT_PTM). By thisoperation, the In-point of the cell is decided. Likewise, the relativetime from the front-end of the VOB to the Out-point (Cell_End_PTM) isacquired. Once the VOB-ID, Cell_StarT_PTM, and Cell_End_PTM, thatidentify the In-point/Out-point, are obtained, this means the generationof cell information. After generation of cell information is performedmore than twice, and an order-assigning operation is performed withrespect to the cell navigators, the cells are assigned playback order,and are disposed in the memory according to the playback order. By thisoperation, a PL is obtained.

The playback control unit 16 displays on the television 101 such as a PGnavigator representing the PG prestored in the DVD, and a PL newlygenerated by the playlist editing unit 15. Then the playback controlunit 16 controls the DVD drive 1 and the MPEG decoder 4, so as toplayback either the PL or the PG, in accordance with the userinstruction in relation to the PG navigator and the PL navigator. Thisplayback control is performed via the following processes. That is, oncethe PL is selected, the playback control unit 16 makes the time-addressconversion unit 13 search for the start addresses respectively for theVOBU including the In-point and the VOBU including the Out-point, basedon the VOB-ID and the relative time of the cell information constitutingthe PL information. Then, the playback control unit 16 instructs the DVDdrive 1 to read from the VOBU including the In-point to the VOBUincluding the Out-point. Then, the playback control unit 16 instructsthe MPEG decoder 4 to playback/output the picture data from the In-pointto the Out-point, among the VOBUs read out in the above way. The sameoperation as above is repeated to all the cells constituting the PL,thereby realizing the playback operation based on the PL.

The non-referenced part extraction unit 17 extracts parts of the VOBthat are not referenced by any of the cells constituting the respectivePLs. Specifically, the parts that the non-referenced part extractionunit 17 extracts are one of (i) from the front-end of the VOB sequenceto immediately before the In-point of any cell, (ii) from immediatelyafter any cell to the rear-end of the VOB sequence, and (iii) fromimmediately after the Out-point of any cell to immediately before theIn-point of the next cell. The non-referenced part extraction unit 17represents the In-point/Out-point of these non-referenced parts, byVOB-ID and relative time from the front-end of the VOB. The reason whythe In-point/Out-point are represented by the VOB-ID and the relativetime from the front-end of the VOB is to maintain the compatibilitybetween the notation systems for the cells. By these operations, listinformation (non-referenced part list) is obtained in whichIn-point/Out-point for non-referenced parts are listed.

The substantial editing unit 18, when instructed to delete any of thenon-referenced parts in the substantial editing menu of FIG. 10, makesthe time-address conversion unit 13 calculate the address of the VOBUincluding the In-point, and the address of the VOBU including theOut-point. Then, the substantial editing unit 18 instructs the DVD drive1, via the time-address conversion unit 13, to delete from the VOBUincluding the In-point to the VOBU including the Out-point. Suchdeletion enlarges the free area of the DVD. Prior to the deletion ofnon-referenced parts, the substantial editing unit 18 makes the DVDdrive 1 read the VOBU including the In-point and the VOBU including theOut-point, and provides instructions so that re-encoding of the In-pointincluding VOBU and the Out-point including VOBU should be performed, sothat these VOBUs will be played back seamlessly. In the re-encoding, theVOBUs that position after the In-point-including VOBU and the VOBUs thatposition before the Out-point-including VOBU have possibility of being atarget of re-encoding. The reason why the VOBUs positioning after theIn-point-including VOBU could be target of re-encoding is that it isprobable that any of these VOBUs include audio frames to be played backin synchronization with the In-point picture data.

In addition, the reason why the VOBUs positioning before theOut-point-including VOBU could be target of re-encoding is that if theseVOBUs include an Open-GOP, and the In-point picture data is one of Bpicture and P picture, it is likely that this B or P picture whichcorresponds to the In-point refers to the picture data among the VOBUsprior to the In-point-including VOBU.

The virtual free-area calculation unit 19, when any of thenon-referenced parts is selected for deletion, displays to the user avirtual free-area size. Please note that incident to the deletion ofnon-referenced part, the amount of data used for re-encoding theIn-point-including VOBU and the Out-point-including VOBU will beadditionally stored in a recording medium. Therefore, in calculation ofa virtual free-area, the size resulting after subtracting thisadditional amount from the data size of the non-referenced part to bedeleted is displayed as the virtual free-area increase.

-   -   i.e. the value obtained by the expression (data size of        non-referenced part)−(size of VOBU obtained by re-encoding) will        be displayed as a virtual free-area increase.

So as to calculate the increase incurred by the re-encoding, the virtualfree-area calculation unit 19, makes the MPEG encoder 3 performre-encoding. Then using thus calculated data size, the virtual free-areacalculation unit 19 displays the virtual free-area calculated in theabove way, to the user. The reason why this value is displayed as avirtual free-area size is that if the non-referenced part is very smallin size, the value obtained by the above expression will be smaller thanthe user expects, which disappoints the user.

The application unit 14 made up of from the playlist editing unit 15 tothe virtual free-area calculation unit 19 is produced by creating acomputer-readable program in which the processes shown in the flowchartsof FIGS. 12, 13, 14, 21, and 22 are written in a computer language (e.g.c-language, machine-language, and Java-language). The processesnecessary to be written for production of the application unit 14 aredescribed with reference to the flowcharts of FIGS. 12, 13, 14, 21, and22. FIG. 12 is a flowchart showing the process performed in the mainroutine of the remote controller. In FIG. 12, after the route menu isdisplayed in Step S10, the control is moved to the loop processcomprised of Steps S1-S3.

Steps S1-S3 performed by the application unit 14 constitute aselection-waiting loop. The process that this loop waits for is such asPL editing, playback process, and substantial editing. If PL editing isselected (Step S1: Yes), the playlist editing unit 15 performs PLediting at Step S4, and obtains a PL. Following this, at Step S5, thenon-referenced part extraction unit 17 extracts as non-referenced part,the part not referenced by any of the cells of the PL in the VOBsequence, and at Step S6, a relative time and an VOB-ID that shows theIn-point/Out-point for the non-referenced part are written into thememory, thereby obtaining a non-referenced part list.

If PG/PL playback processes are selected, the playback control unit 16,at Step S7, displays the PG playback menu and the PL playback menu, forthe user to select either a PL or a PG. Then, the playback control unit16, at Step S8, instructs the DVD drive 1 and the MPEG decoder 4 to playback the PL/PG selected at Step S8. If substantial editing is selected,the substantial editing unit 18, at Step S9, deletes the non-referencedpart shown in the non-referenced part list, thereby obtaining a freearea.

Next, with reference to FIG. 13, the process performed by the playlistediting is described. FIG. 13 is a flowchart showing the processperformed by the playlist editing unit 15.

In the flowchart of FIG. 13, at Step S11, the playlist editing menuincluding such as a slide bar and a window is displayed. Then, accordingto instruction given by one of left/right key presses (Step S12), anIn-point/Out-point deciding button press (Step S13), and a return keypress (Step S14), the processes of Steps S15-S17, Steps S18-S23, andSteps S24-S29 are selectively performed.

Specifically, at Steps S15-S17, the slide bar is slid for a unit lengthin the direction of the pressed key (Step S15) Every time the slide baris slid in the unit length, the position of the slide bar on the guideis converted into a VOB-ID and a relative time (Step S16). Thisoperation is for reducing and then displaying in the window, the picturedata identified by the VOB-ID and the relative time (Step S17).

In the aforementioned Steps S15-S17, as long as the left/right press iscontinuing, the slide bar will be continually slid. Then, the picturedata corresponding to where the slide bar is will be displayed in thewindow. According to this operation, the user decides the desiredposition as an alternative for the In-point/Outpoint.

Steps S18-S23 are for deciding the position of the slide bar asIn-point/Out-point, at the time when the In-point/Out-point decidingbutton is pressed. Prior to this decision, judgment is performed as towhether the In-point already exists (Step S18), and if judgment resultsin the negative, the position of the slide bar is converted into aVOB-ID and a relative time (Step S19), and the VOB-ID and the relativetime obtained by the conversion are set in the cell information asIn-point (Step S20).

If the corresponding In-point has been already set, the position of theslide bar in the guide is converted into a VOB-ID and a relative time(Step S21), and the VOB-ID and the relative time are set in the cellinformation as Out-point (Step S22). Then, the cell information showingthe In-point/Outpoint is written to the memory. Then, a cell navigatormade up of the In-point/Out-point is displayed (Step S23).

By repeating a series of processes in which the slide bar is moved andthe In-point/Out-point deciding button is pressed, pieces of cellinformation are sequentially generated, and a plurality of cellnavigators appear on the menu.

Steps S24-S29 are for generating a plurality of cell navigators, whichare performed when the return key is pressed. In Steps S24-S29, thenumerical value fields for the corresponding cell navigators are set tobe in an active state (step S26), and a numeric value input is waited(Step S27). If a numeric value is inputted, the inputted numeric valueis set as a playback order in the corresponding cell (Step S28). Theprocesses mentioned so far are repeated for a plurality of cellnavigators (Step S24, S25). When the playback order for all the cells isset, the pieces of cell information are disposed according to thisplayback order, thereby obtaining PL information (Step S29). This is theend of description about the playlist editing.

As follows, the processes for extracting non-referenced part aredescribed with reference to the flowchart of FIG. 14. FIG. 14 is aflowchart showing the processes performed by the substantial editingunit 18. In this flowchart, the variable “i” is for identifyingnon-referenced part that is extractable, and “#x” is among the cellsbelonging to the PL, and works as a variable for representing adelimiter of non-referenced part.

After the variable “i” is reset to an initial value 1, judgment as towhether the beginning part of the VOB sequence should be non-referencedpart is performed at Step S31. This step specifically is for judgingwhether the case is FIG. 15A or FIG. 15B. FIG. 15A is a case where thebeginning part of the VOB sequence is specified as a cell of a PL. FIG.15B is a case where the beginning part of the VOB sequence is notspecified as a cell of any PL. In the case of FIG. 15B, the beginningpart of the VOB sequence can be a non-referenced part.

If there is no cell that has the front-end of the VOB sequence specifiedas In-point, then at Step S33, the beginning part of the VOB sequence isset to be the In-point of the non-referenced part “i”, as shown by thearrow sign ky1 of FIG. 15B. Then, at Step S34, among the cells #1-#nthat belong to one PL, the cell that has the In-point appearing firstwill be specified as Cell#x, as shown by the arrow sign ky2. At StepS35, the part before the Cell#x is delimited as a non-referenced part.

The delimiting is performed so that the point immediately before theIn-point of the Cell#x is specified as Out-point of the non-referencedpart “i”, as shown by the arrow sign ky3 of FIG. 15B (Step S35). Bydoing this, as shown by the arrow sign ky4, the part shown by hatchpattern is decided as non-referenced part, and the control is moved toStep S37.

If there is no cell, in any PL, that specifies the front-end of the VOBsequence as In-point, it is impossible to specify the beginning part ofthe VOB sequence to be non-referenced part. Therefore, at Step S36, thecell whose In-point is the front-end of the VOB sequence is specified asCell#x, as shown by the arrow sign ky5, and the control is moved to StepS37.

Step S37 plays a role of an entrance to the loop operation made up ofSteps S37-S43, by being positioned at the intersection between theprocesses performed at Steps S33-S35 and the process of Step S36.

Specifically this loop operation is an incessant repetition of theprocesses described as follows. First, the point immediately after theOut-point of the Cell#x is set as In-point of the non-referenced part“i” (Step S40), and the cell positioning after the In-point of thenon-referenced part “i” is set as a new Cell#x (Step S41, Step S42), andthe point immediately before the In-point of the new Cell#x is set asthe Out-point of the non-referenced part “i” (Step S43).

The variable “i” specifying the non-referenced part is incremented atStep S39. That is, the variable “i” is incremented every time this loopoperation ends one loop, and the part between the former Cell#x and thenew Cell#x to be ith non-referenced part is specified as non-referencedpart. FIG. 16 is a diagram showing how non-referenced parts arespecified by the repetition of this loop operation.

The Cell#x in this diagram does not have any cell that positionsimmediately after, nor have any overlapping cell. Therefore, at StepS40, the point immediately after the Out-point is set to be the In-pointof the non-referenced part “i”, as shown by the arrow sign ty1. Then,the cell#y that positions after the In-point of the non-referenced part“i” and that is the nearest to this In-point is set to be a new Cell#x,as shown by the arrow sign ty2 (Step S41, Step S42). The pointimmediately before the In-point of the new Cell#x is set to be theOut-point of the non-referenced part “i” (Step S43). By doing this, thepart shown by hatch pattern is decided as a non-referenced part, asshown by the arrow sign ty3. After this, the same operation is repeatedfor the cells that come after this new Cell#x. These are the contents ofthe loop operation of Steps S37-S43.

The conditions for ending this loop operation are that: the Out-point ofthe Cell#x coincides with the rear-end of the VOB sequence (Step S37:Yes); and within any PL, no cell exists whose In-point positions afterthe In-point of the non-referenced part “i” (Step S41: No). Unless theseending conditions are met, this loop operation will be repeated.

FIGS. 17A and 17B are diagrams showing the two cases that satisfy theending conditions of the loop operation. FIG. 17A is a case in which theOut-point of the Cell#x coincides with the rear-end of the VOB sequence.In this case, after the operation of this flowchart is ended, thecontrol will return to the main routine. FIG. 17B is a case in which theOut-point of the Cell#x does not coincide with the rear-end of the VOBsequence. In this case, at Step S40 in the loop operation, the pointimmediately after the Out-point of the Cell#x is set to be the In-pointof a non-referenced part, as shown by the arrow sign hy1. Accordingly,as shown by the arrow sign hy2, the rear-end of the VOB sequence is setto be the Out-point of the non-referenced part. As a result of theseoperations, the non-referenced part is decided as shown by the arrowsign hy3.

The above description is based on the premise that there is nooverlapping cell with the Cell#x, and there is no cell that positionsimmediately after the Cell#x. If such an overlapping cell, or the cellthat positions immediately after the Cell#x exists (Step S38: Yes), thenStep S38 and Step S44 constitute a loop operation. This loop operationis to be performed prior to executing Steps S39-S43. Unless the controlwill pass through Steps S38-S44, Steps S39-S43 will not be performed.Steps S38-S44 are for repeating the operations of setting a cell thatoverlaps with the Cell#x, and a cell that positions immediately afterthe Cell#x, to be a new Cell#x (Step S44).

FIGS. 18 and 19 are diagrams showing the cases in which the processes ofSteps S38-S44 are repeated. The cell that can be a new cell in StepsS38-S44 is Cell#w or Cell #z, respectively shown in FIGS. 18 and 19. TheCell#w in FIG. 18A has In-point immediately after the Cell#x, and hasOut-point after the Out-point of the Cell#x. The Cell#z in FIG. 19 hasIn-point within the Cell#x and has Out-point after the Out-point of theCell#x. These Cell#w and Cell#z cannot be delimiters of non-referencedpart, even if these cells come after the Cell#x. This Step S44 decidescells that do not work as a delimiter of non-referenced part, and skipsthese cells. According to this skip, Cell#w and Cell#z of FIGS. 18A and19A are made to be respective new Cells#x, as shown by the arrow signsty2 and ty3.

As a result of these skips, free areas respectively following the newCells#x are set to be non-referenced part.

One condition for ending this loop operation is that: the Cell#x hasreached to where there is no overlapping cell with the Cell#x, and towhere there is no cell that positions immediately after the Cell#x.Another ending condition is that, from the beginning, there is nooverlapping cell with the Cell#x, and that there is no cell thatpositions immediately after the Cell#x. In this case, Step S38 is No,and the control is moved to Steps S39-S43.

The processes performed in the above flowchart are described in greaterdetail, with reference to the concrete example depicted in FIG. 20. Theconcrete example of FIG. 20 is based on the premise of FIG. 3 and FIG.4, in which two PLs, namely, PL#1 and PL#2 are defined on the VOBsequence. The PL#1 is made up of two cells, namely Cell#1-Cell#2. ThePL#2 is made up of three cells, namely Cell#1-Cell#2-Cell#3. PL#1-Cell#1and PL#2-Cell#1 overlap with each other. Likewise, PL#1-Cell#2 andPL#2-Cell#2 overlap with each other. The note “i=1, i=2, i=3, i=4” andthe like indicates that, if the variable “i” takes a value such as 1, 2,3, and 4, which part of the VOB sequence is extracted as non-referencedpart.

In addition, the note “#x (nth time)” indicates that the cell detectedas Cell#x in nth time is which cell of which PL.

If the non-referenced part extraction unit 17 performs an operation onthe concrete example of FIG. 20, at Step S31, it is judged that there isno cell, within any PL, whose In-point corresponds to the front-end ofthe VOB sequence. At Step S33, the front-end of the VOB sequence is setas the In-point of the first non-referenced part #1. Since the cell thathas the In-point nearest to this In-point is PL#2-Cell#1, at Step S34,PL#2-Cell#1 is specified as the first Cell#x. Then, at Step S35, theOut-point of the first non-referenced part (i=1) is set to beimmediately before the In-point of PL#2-Cell#1.

Following this, the loop operation of Steps S37-S43 is executed. Thecell that overlaps with PL#2-Cell#1 is Cell#1 of PL#1. This Cell#1 ofPL#1 has Out-point which positions after Cell#2 of PL#2. Therefore, atStep S38 and at Step S44, PL#1-Cell#1 is newly set to be the secondCell#x. Since there is no overlapping cell with this Cell#1 of Pl#1, atStep S40, the point immediately after the Out-point of PL#1-Cell#1 isspecified as the In-point of the second non-referenced part (i=2).

At Steps S41 and S42, PL#2-Cell#2 is set as a new Cell#x, since thiscell is the cell whose In-point positions after and nearest to theIn-point of the second non-referenced part. At Step S43, the pointimmediately before the In-point of PL#2-Cell#2 is specified as theOut-point of the second non-referenced part, then the control is movedto Step S37.

The cell that overlaps with PL#2-Cell#2 is Cell#2 of PL#1. ThisPL#1-Cell#2 has Out-point that positions after the Cell#2 of PL#2.Therefore at Step S42, PL#1-Cell#2 is set to be a new Cell#x. Sincethere is no overlapping cell with PL#1-Cell#2, at Step S40, the pointimmediately after the Out-point of PL#1-Cell#2 is specified as theIn-point of the third non-referenced part (i=3).

The cell whose In-point positions after and nearest to the In-point ofthe third non-referenced part is PL#2-Cell#3. Therefore, PL#2-Cell#3 isset as the third Cell#x (Step S41, Step S42), and the In-point ofPL#2-Cell#3 is set as the Out-point of the third non-referenced part(Step S43).

There is no cell that overlaps with this PL#2-Cell#3 (Step S41: No). Inaddition, there is no cell that positions after PL#2-Cell#3. Therefore,the Out-point of PL#2-Cell#3 is specified as the In-point of the fourthnon-referenced part (i=4), and the rear-end of the VOB sequence isspecified as the Out-point of the fourth non-referenced part (Step S43).

This is the end of description about the process of extractingnon-referenced part. Following this, the substantial editing isdescribed with reference to FIG. 21. FIG. 21 is a flowchart showing theprocess performed by the substantial editing unit 18. First, asubstantial editing menu comprised of non-referenced part navigatorseach graphically representing a non-referenced part (Step S51). Then thetop non-referenced part is set to be in a focus state (Step S52), andwaits for an event to occur, such as an up/down key press (Step S53), aplayback key (Step S54), a decision key (Step S55), deciding operationfor a batch deletion button (Step S56), and a return key press (StepS57).

If an event of the up/down key press occurs (Step S53: Yes), then thenon-referenced part currently in a focus state is set to be in a normalstate, and the non-referenced part positioning in the decision keydirection is set to be in a focus state (Step S58), and the controlreturns to an event-waiting loop comprised of Steps S53-S57.Hereinafter, the state for each non-referenced part will change whilethe up/down is being pressed.

If the playback key is pressed (Step S54: Yes), an operation isperformed in which the non-referenced part is played back and thecontent of the non-referenced part is displayed to the user.Specifically, at Step S59, playback of from the In-point to theOut-point of the non-referenced part “k” that is in a focus state isinstructed to the DVD drive 1 and to the MPEG decoder 4. This playbackcontrol is performed through the following processes. That is, if any ofthe non-referenced parts is in a focus state, and the playback key ispressed, the playback control unit 16 makes the time-address conversionunit 13 search for the start addresses respectively for the VOBUincluding the In-point, and the VOBU including the Out-point, based onthe VOB-ID and the relative time that identifies the In-point/Out-pointof the non-referenced part, and orders the DVD drive 1 to read out fromthe VOBU including the In-point to the VOBU including the Out-point.Then the MPEG decoder 4 is ordered to output, for the purpose ofplayback, from the picture data corresponding to the In-point to thepicture data corresponding to the Out-point, among the read VOBUS. Bydoing this, the non-referenced part is displayed at the television 101,and the user can judge whether the non-referenced part is necessary ornot.

If the decision key is pressed (Step S55: Yes), the non-referenced partthat is in an active state is set as non-referenced part “k” (Step S60),and the VOBU including the In-point for the non-referenced part “k” andthe VOBU including the Out-point of the non-referenced part “k” are readout and re-encoded (Step S61). Then, the value obtained by theexpression (size of non-referenced part)−(VOBU size after re-encoding)is displayed as a virtual free area size (Step S62), then the controlwaits for receiving a deletion confirmation operation from the user(Step S63).

When the deletion confirmation operation from the user is received, fromthe VOBU including the In-point to the VOBU including the Out-point aredeleted (Step S64), and new VOBUs obtained by re-encoding are writtenback to the DVD (Step S65).

A free area is obtained by the deletion of VOBUs at Step S64. Afterthis, once the MPEG encoder 3 encodes a broadcast signal that the tuner2 has demodulated, thereby obtaining a new VOB, this new VOB can bewritten to this free area.

If the deciding operation for the batch deletion button for thenon-referenced part is indicated (Step S56: Yes), Step S66 is performed.Step S66 has a sub-routine thereunder. FIG. 22 is a flowchart showingthe process regarding this batch deletion of non-referenced part in DVD.

In this flowchart, first, the loop operation from Steps S142-S144 isperformed. This loop operation is a repetition of the followingprocesses for all the non-referenced parts included in the DVD (StepsS142, and S143). The specific processes are in which the VOBU includingthe In-point of the non-referenced part “k” and the VOBU including theOut-point of the non-referenced part “k” are read out, and thenre-encoding is performed on the read VOBUs (Step S144).

Once this re-encoding is finished, at Step S145, the value resultingfrom the expression (summation of sizes of all non-referencedparts)−(summation of VOBU sizes after re-encoding) is displayed, on thesubstantial editing menu, as a virtual free area size.

Once the deletion confirmation operation is received from the user, andthe deletion confirmation operation from the user completes, the loopoperation from Steps S147-S150 is performed. Specifically, the VOBUsfrom the VOBU including the In-point to the VOBU including the Out-pointare deleted (Step S149), and new VOBUs obtained by re-encoding, arewritten back to the DVD (Step S150). In the loop operation, the aboveoperations are repeated for all the non-referenced parts belonging to aPG (Steps S147, and S148). After finishing this repetition, the controlwill return to the main routine.

As described above, according to the present embodiment, a plurality ofnon-referenced parts are displayed to a user, among which the user canselect parts to be deleted. This enables selective deletion in whichnon-referenced parts whose preservation value is relatively low areabandoned. With this construction, it becomes possible to keep the userfrom regretting as much as possible, and also to allocate free spaces.

According to such a substantial editing, if there is a small deficiencyin free space for the purpose of another recording, free space can beallocated by deleting some of the extracted non-referenced parts. Thiswill prevent the opportunity of recording new broadcast contents to slipaway.

The Second Embodiment

In the first embodiment, deletion of non-referenced part is performed atthe time of executing the substantial editing. This means that in thefirst embodiment, unless the user shows definite intention for selectingthe substantial editing, deletion of non-referenced part will not beperformed. It is not probable that the user, who is wishing to allocatefree areas, nevertheless is not fully aware of the non-referenced parts,will choose to perform the substantial editing with a definiteintention. Accordingly, it is not possible to prompt such a user todelete non-referenced part. In view of this, in the second embodiment,at the time of performing an operation for playback a PG, the user willbe informed of whether there is non-referenced part for each PG. Asmentioned above, the non-referenced part is a part not referenced by anyPL, and so cannot be displayed at PL playback. It is only at PGplayback, that such a non-referenced part is displayed. In the secondembodiment, the user will be informed of whether there is non-referencedpart for each PG with use of PG navigator, at the time when user showsintention to perform PG playback.

FIG. 23 is a diagram showing PG navigator relating to the secondembodiment. The PG navigator relating to the second embodiment appearsat the television 101 when the user has selected the PG playback in theroute menu, just as in the first embodiment. The difference of PGnavigator in this diagram, from that of FIG. 6 or from FIG. 8, is (i)the positive/negative marks mr1, mr2, and mr3 exist, and (ii) thesetting menu my1 unique to PG can be drawn out.

The positive/negative marks mr1, mr2, and mr3 each show that there is“negative” part that symbolizes non-referenced part in the PG. Theexample of FIG. 23 indicates that the contents 1, 2, and 3 either havenon-referenced part therein, or that the PG itself is non-referencedpart.

The setting menu drawn out from each PG navigator receives selection ofsuch as one of the following items: PG deletion (1) for deleting wholePG from the DVD; partial PG deletion (2) for deleting only a part of PG;PG protect (3) for setting the attribute of PG as deletion inhibit;title input (4) for receiving title input with regard to PG; andnon-referenced part batch deletion (5) for deleting all thenon-referenced parts included in PG at once. The setting menu in thisdiagram is for the PG navigators that are assigned a positive/negativemark. The setting menu for the PG navigators that are not assigned apositive/negative mark will have only items (1)-(4) stated above. Thereason for this is that for the PG that does not have any non-referencedpart, it is not necessary, from the beginning, to delete non-referencedpart.

Because the non-referenced part, by definition, is a part not referencedby the PL, therefore is assumed to have low preservation value. It islikely that sooner or later, non-referenced parts are to be deleted. Ifthese non-referenced parts are deleted prior to the PG playback, the PGis played back in a refined state without non-referenced part.

The flowchart for PG playback that relates to the second embodiment isshown in FIG. 24. This flowchart is for realizing PG playback, and is analternative for Steps S7 and S8 of the main routine of FIG. 12.

In this flowchart, a plurality of PG navigators are displayed in theloop operation comprised of Steps S70-S75. After the front-end PG is setin a focus state at Step S75, an event is waited at the loop operationof Steps S76-S79. According to the event that has occurred after thisevent waiting, one of Steps S8, S79, S80-S86 is selectively performed.

The loop operation comprised of Steps S70-S74 repeats, for all the PGsrecorded in the DVD, operations of: judging whether the PG itself is anon-referenced part, or there is non-referenced part within the PG (StepS72); and disposing a PG navigator without a positive/negative mark, forthe PG judged not to include non-referenced part therein (Step S73), anddisposing a PG navigator with a positive-negative mark, for the PGjudged to include non-referenced part therein (Step S74). As a result ofthis loop operation of Steps S70-S74, the front-end navigator among theplurality of PG navigators is set to be in a focus state (Step S75).

The event-waiting loop of Steps S76-S77 is to, according to an up/downkey press (Step S76), wait for a decision key press (Step S77), and aright key press (Step S78), while changing the state of each PGnavigator (Step S79). The state change of PG navigators is to return thePG currently in focus state to normal state, and the PG positioning inthe key direction to focus state. If the decision key is pressed whileany of the PG navigators is in focus state, the PG in focus state isplayed back at Step S8.

If the right key is pressed, both of the setting menu display (StepsS80-S82) and the operation incident to the operation for this menu(Steps S83-S86) are performed.

In the setting menu display, the PG setting menu having items such as PGdeletion (1), partial PG deletion (2), PG protect (3), and title input(4) is first drawn to the right hand side of the PG in focus state (StepS80), then if the PG in focus state has non-referenced part therein(Step S81: Yes), the item of “non-referenced part batch deletion (5)” isadded (Step S82).

By this setting menu display, the setting menu for PGs that do not havenon-referenced part therein will have PG deletion (1), partial PGdeletion (2), PG protect (3), and title input (4). Whereas the settingmenu for PGs that have non-referenced part therein will havenon-referenced part batch deletion (5), in addition to the items(1)-(4).

In the operation that is incident to the operation for the setting menu,firstly, input for the items shown in the setting menu is waited (StepS83), and if the selected item is the non-referenced part batch deletion(5), the substantial editing directed to the non-referenced partbelonging to the PG is performed (Step S86). On the other hand, if theselected item is one of the items (1)-(4), then the correspondingoperation is performed (Step S85).

As described so far, by the present embodiment, the batch deletion ofnon-referenced part included in a PG is prompted to the user, prior tothe playback of the PG. Therefore, deletion of non-referenced part isfacilitated.

The Third Embodiment

In the second embodiment, deletion of non-referenced part included in aPG is prompted when a user shows intention to play back the PG. In thethird embodiment, deletion of non-referenced part included in each PG isalso prompted to a user showing the intention of PG playback. Thedifference with the second embodiment is to provide a check box in eachPG navigator, and executes deletion of non-referenced part in each PG,according to the check operation with respect to this check box.

FIG. 25 is a diagram showing one example of PG navigator relating to thethird embodiment. Just as in the first embodiment, the PG navigator willappear in the television 101 after the user selects PG playback in theroute menu. The difference with the PG navigator shown in FIG. 23 isthat, instead of the positive/negative mark, the check boxes ch1, ch2,and ch3 are provided. The check mark placed in this checkbox indicatesthat the user has shown his intention of deleting all the non-referencedparts within the corresponding PG. The check boxes ch1, ch2, and ch3will be displayed for each of the PGs having non-referenced part.Therefore, if the user wants to delete the non-referenced parts inseveral PGs at once, all he has to do is to check the check boxescorresponding to these PGs. In this diagram, the first PG and the thirdPG have a check mark in their check boxes. Therefore, the non-referencedparts in the content 1 and content 3 are to be deleted at once.

The batch deletion button is1 is a GUI part assigned to such as thepicture-recording key and the playback key, of the remote controller,and is for receiving the operation such as of deleting thenon-referenced parts displayed in the menu, at once.

The playback operation for the PG navigators assigned the aforementionedcheck box is realized as described in the flowchart of FIG. 26.Hereafter, the process performed by the recording apparatus of the thirdembodiment is described with reference to this flowchart. The flowchartof FIG. 26 is created based on the flowchart of FIG. 24. Therefore, thesteps that perform the same operation as in the flowchart of FIG. 24 areassigned the same reference number, and the description thereof isomitted.

In the flowchart of FIG. 26, a plurality of PG navigators are displayedas a result of the loop operation comprised of Steps S70-S73, and StepsS126. Then, after the front-end PG is set in a focus state at Step S75,an event is waited at the loop operation of Steps S76-S77, and StepsS120-S121. According to the event occurring after this event waiting,one of Steps S8, S79, S122, S123-S125 is selectively performed.

The loop operation comprised of Steps S70-S75 is for repeating, for allthe PGs recorded in the DVD, the following operations of: judgingwhether the PG itself is a non-referenced part, or whether there isnon-referenced part within the PG (Step S72); and disposing a PGnavigator without a check box, for the PG judged not to includenon-referenced part (Step S73), and disposing a PG navigator with acheck box, for the PG judged to include non-referenced part (Step S126).After this loop operation of Steps S70-S73, and S126, the front-end PGnavigator among the plurality of PG navigators is set to be in a focusstate (Step S75).

The event-waiting loop of Step S76-S77 is for, according to an up/downkey press (Step S76), waiting for a decision key press (Step S77), acheck operation for the check box (Step S120), and a batch-deletionbutton decision operation (Step S121), while changing the state of eachPG navigator (Step S79). The state change of PG navigator is tospecifically return the PG currently in focus state to normal state, andto set the PG positioning in the key direction to focus state (StepS79). If the decision key is pressed when any of the PG navigators isset in a focus state, the PG in a focus state is played back at Step S8.

If a check operation is performed to the check box (Step S120), a checkmark is placed in the check box (Step S122), then the control returns tothe loop operation comprised of Steps S76-S77, and S120-S121.

If a batch-deletion button deciding operation is performed (Step S121:Yes), the following operations are repeatedly performed for all the PGswhose check box is checked (Steps S124, and S125). The operations arespecifically for: confirming the existence of check mark in the checkbox (Step S123); and performing substantial editing directed to thenon-referenced part included in the PG (Step S126).

As described above, according to the present embodiment, the PGs whosenon-referenced part should be deleted may be collectively defined,thereby enhancing the convenience for the user.

The Fourth Embodiment

The fourth embodiment is for prompting cleanup of non-referenced partwhen a recording programming is performed with respect to the recordingapparatus. A recording programming is performed in response to receptionfrom a user the input of the recording start date/time and recording enddate/time. In the recording programming, once the recording startdate/time, recording end date/time, and image-quality mode are set, itis possible to calculate the size necessary for the content recording.However, when the calculated size exceeds the free area size currentlyremaining in the DVD, conventional DVD recorders cannot perform theprogrammed recording. In view of this, in this fourth embodiment, afterthe items such as recording start date/time-recording end date/time areset and size required for the recording is calculated, the user will beprompted to delete non-referenced part, if the calculated size exceedsthe free area size of the DVD.

The recording programming operation is performed for the menu shown inFIG. 27. FIG. 27 is a diagram showing one example of the recordingprogramming menu. The recording programming menu is made up of:numerical value fields nr1, nr2, nr3, and nr4, in which date/time tostart recording is defined as a representation of “month” “day” “time”and “minute”; numerical value fields ur1, ur2, ur3, and ur4, in whichdate/time to end the recording is defined as a representation of “month”“day” “time” and “minute”; a numerical value field cr1 in which thebroadcast channel to be recorded is defined as a numerical value; andbuttons bn3, 4, 5, and 6, for respectively receiving one of the fouralternatives of image-quality mode (i.e. 1.6 Mbps (Economy low quality),2.4 Mbps (Long-hour low quality), 4.7 Mbps (Standard quality), and 9.5Mbps (High quality)).

If recording programming is performed for this menu, playback time andsize of the content to be recorded are obtained. When the obtained sizeis below the free area size of the DVD, the recording is performedaccording to the programming performed in this menu.

If the obtained size exceeds the free area size of the DVD, the userwill be prompted to delete the non-referenced parts included in the DVD.The menu wr1 is a warning dialogue displayed when lack in free area isrevealed during the recording programming. In the fourth embodiment,deletion of non-referenced part is performed when the user gives anaffirmative answer to this menu. If the user answers negatively to thismenu, the menu wr2 will be displayed.

The recording programming operation for this menu of FIG. 27 isperformed according to the flowchart of FIG. 28. As follows, thisrecording programming operation is described with reference to thisflowchart.

In this flowchart, a series of operations for recording programming areperformed, the series of operations including: input of recording startdate/time (Step S91); input of recording end date/time (Step S92); inputof reception channel (Step S93); and setting of image-quality mode (StepS94). Then, an area size necessary for performing the programmedrecording is calculated (Steps S95-S97), and judgment is performed as towhether the DVD has enough free area required for the programmedrecording (Steps S98-S101). After completion of the above, deletion ofnon-referenced part is performed when there is lack in free area in theDVD and after the confirmation of the user is received (StepsS102-S104).

Calculation of necessary area size performed at Steps S95-S97 is to setthe bit rate based on the recording mode set at the menu (Step S95),calculate the playback time in the unit of second, from the calculationof “recording end date/time-recording start date/time” (Step S96), thenperforms calculation of “the playback time multiplied by bit rate”thereby obtaining the area size required for the recording (Step S97).

The judgment as to whether there is enough DVD free area performed atSteps S98-S101 is to serially perform the following: a judgment as towhether the DVD free area exceeds the required area size for recording(Step S99); and a judgment as to whether the summation of non-referencedparts is below the required area size for recording (Step S101).

If at Step S99 the DVD free area size is judged to exceed the requiredarea size for the recording, the control returns to the main routinefrom the operations in this flowchart. Judgment of Step S101 is onlyperformed when the DVD free area size is below the required size forrecording.

Specifically, when the DVD free area size is below the required areasize for recording, the summation of non-referenced parts in the DVD iscalculated (Step S100), and at Step S101, judgment is performed as towhether the summation of non-referenced parts is below the required areasize for recording. If the summation is judged to exceed the requiredsize for recording, the dialogue prompting the deletion ofnon-referenced parts is popped up (Step S102), so as to confirm the userof the deletion (Step S103). If the user agrees with performing of thisdeletion, all the non-referenced parts in the DVD are deleted (StepS104).

If the summation of non-referenced parts exceeds the required area sizefor recording, and if the user does not agree with performing of thedeletion, the user will be notified that it is impossible to perform therecording at Step S105.

As described above, according to the present embodiment, deletion ofnon-referenced part is prompted, if the user shows intention ofrecording programming, and that there is lack in free area in the DVD.This construction facilitates cleanup of non-referenced parts.

The Fifth Embodiment

The fifth embodiment discloses a recording apparatus capable ofperforming environment setting. This environment setting performed bythe recording apparatus is to receive a setting of a minimum size offree area that the user wants to allocate, and to store the minimum sizeas the environment setting. The recording apparatus keeps monitoring thefree area size that the DVD currently has. If the free area size fallsbelow this environment setting, the recording apparatus pops up awarning dialogue, thereby prompting deletion of non-referenced part.

Environment setting performed by a user will be done for the environmentsetting menu shown in FIG. 29. FIG. 29 is a diagram showing one exampleof menu used in the fifth embodiment.

The route menu rm1 in FIG. 29 includes the item of “environmentsetting”, in addition to “PG playback”, “PL playback”, “playlistediting”, and “substantial editing” that the first embodiment has. Theenvironment setting menu will be displayed when this “environmentsetting” is selected at the route menu rm1.

The environment setting menu ev1 includes: buttons bn1 and 2, forreceiving selection of two alternatives of specification by byte sizeand specification by time; a numerical value input field nm1 forreceiving specification of size of area to be allocated in the unit ofbyte; a numerical value input field nm2 for receiving specification ofplayback time in the unit of minute; and buttons bn3, 4, 5, and 6, forrespectively receiving one of the four alternatives of image-qualitymode (i.e. 1.6 Mbps (Economy low quality), 2.4 Mbps (Long-hour lowquality), 4.7 Mbps (Standard quality), and 9.5 Mbps (High quality)). Theinput operation directed to the buttons and the numerical value fieldsis performed based on the flowchart of FIG. 14.

The warning dialogue wr3 is displayed when the environment setting valueset in the environment-setting menu cannot be allocated.

The process performed by the recording apparatus in the fifth embodimentis shown in the flowcharts of FIGS. 30 and 31. As follows, the processperformed by the recording apparatus of the fifth embodiment isdescribed with reference to these flowcharts. The flowchart of FIG. 30corresponds to the main routine, and is based on the flowchart of FIG.12 that is for the first embodiment. Since being based on FIG. 12, theflowchart of FIG. 30 shares the same steps. As follows, the same stepsare assigned the same reference number, and the description thereof isomitted.

The flowchart of FIG. 30 executes the loop operation comprised of StepsS1-S3, and S111-S112. Once the environment setting is selected (StepS111: Yes), input of environment setting is received, in accordance withthe flowchart of FIG. 31.

In the flowchart of FIG. 31, the area allocation menu of FIG. 29 isdisplayed first at Step S121, and then the control is moved to the loopoperation of Steps S122-S123. If the button bn1 for specifying the bytesize is clicked (Step S123), numerical value input is made to beeffective which enables input of numerical value from among 0-4.7 in thenumerical value input field nm1 (Step S124), and the inputted numericalvalue is interpreted as the minimum free area size k (Step S125).

If the button bn2 for specifying time is clicked (Step S122), numericalvalue input from among 0-120 minutes is made to be effective in thenumerical value input field nm2 (Step S126). After the input isperformed therein, the image-quality mode buttons bn3-6 are made to beeffective, which are for selecting one of the four image-quality modealternatives (Step S127). Then when a playback time and an image-qualitymode are specified, the minimum free area size k is calculated by themultiplication of “bit rate of the specified image quality and theplayback time corresponding to the numerical value inputted” (StepS128). The free area size calculated in the above way is stored as anenvironment setting.

When it reaches the monitor time that the timer has set in advance inthe loop operation comprised of Steps S1-S3, and S111-S112, the freearea size in the DVD is detected (Step S114), and the judgment as towhether the free area size in the DVD exceeds the environment settingvalue. If the size is judged to exceed the environment setting value,the control returns to the loop operation comprised of Steps S1-S3, andS111-S112.

If the size is judged not to exceed the environment setting value, batchdeletion is performed for the non-referenced parts within the DVD, ifthe deletion execution is selected (Step S118). If the deletionexecution is not selected, it is displayed to the user that the minimumfree area size cannot be allocated (Step S119).

As described in the above, according to the present embodiment, thesetting of the free area size in the DVD is received from a user as anenvironment setting, and the user will be prompted to deletenon-referenced part when the actual free area size falls below thisenvironment setting value. Therefore it becomes possible to facilitatecleanup of non-referenced part.

The Sixth Embodiment

The substantial editing of the first embodiment only deletesnon-referenced part. However, non-referenced part sometimes includescontents worthy of being preserved. Users often notice its value duringthe substantial editing. In view of this, the sixth embodiment performsoperation so as to incorporate a non-referenced part into the PL when auser notices the preservation value of the non-referenced part duringthe substantial editing. FIG. 32 is a flowchart showing the operationperformed by the substantial editing unit 18 relating to the sixthembodiment. In this flowchart, what are new are as follows. That is,Step S131 is inserted between Step S55 and Step S60, and an instructionis received from a user as to whether the non-referenced part k in afocus state should be converted into a referenced part (i), and if theuser answers affirmatively, the operation of Steps S132-S135 isperformed (ii).

As follows, the operation of Steps S132-S135 in FIG. 32 is described. AtStep S131, if the user performs an operation for converting thenon-referenced part k in a focus state into a referenced part, thesubstantial editing unit 18 displays a list of PL navigators (StepS132). This operation is for prompting the user to define the positionto which the non-referenced part is to be returned. After the display ofPL navigators, specification of a cell to which the non-referenced partk will be returned is received (Step S133). Following this, theinformation specifying the In-point/Out-point of the non-referenced partk is converted into cell information r (Step S134), and the cellinformation r obtained by the conversion is inserted between the cell pwhose specification is received and the cell p+1 that followsimmediately after (Step S135). According to the processes describedabove, the non-referenced part whose preservation value was noticedduring substantial editing is incorporated as a member of the PL.

As follows, with reference to the concrete examples in FIG. 33 and FIG.34, the operation performed by the substantial editing unit 18 of thesixth embodiment is described. In this FIG. 33, suppose thenon-referenced part #3 is defined as the non-referenced part #r, andthat the Cell#1 of the PL is specified as a cell in which this cellinformation #r is to be inserted. In this case, the Cell#1 of the PL isspecified as cell information #p, and the Cell#2 is specified as cellinformation #p+1. Then, as shown in FIG. 34, the cell information of thecell #r is generated from the information specifying theIn-point/Out-point of the cell information #r, and thus generated cellinformation #r is inserted between the cell information #p and the cellinformation #p+1. By doing this, part of the VOB never having beenreferenced by any PL so far can be included as a member of a PL.

As described above, according to the present embodiment, it is possibleto convert the non-referenced part that the substantial editing unit 18has extracted, into cell information, thereby including the cellinformation as a member of a PL. Therefore the convenience of editingwill be enhanced.

The Seventh Embodiment

The seventh embodiment is for executing so-called “undo function” ofediting. To realize this undo function, the recording apparatus thatrelates to the seventh embodiment is equipped with a nonvolatile memory,and the substantial editing unit 18 obtains, in this memory, the backupof from the VOBU including the In-point of the non-referenced part tothe VOBU including the Out-point of the non-referenced part. Byretaining the backup in the nonvolatile memory, it becomes possible torestore the deleted non-referenced part to the DVD, unless the contentsof the nonvolatile memory are deleted.

The substantial editing unit 18 displays the button for undo function onthe substantial editing menu, and writes back the VOBU from thenonvolatile memory to the DVD, in response to a press of this button.According to this construction, non-referenced parts having been oncedeleted can be restored to the DVD.

As described above, according to the present embodiment, non-referencedpart is deleted after being saved to the nonvolatile memory. Therefore,if the user notices the value of the deleted non-referenced part, thepart can be restored to the DVD.

In addition, only the non-referenced part having been actually deletedare backed up for the undo function, meaning that not all the pluralityof non-referenced parts should be retained in the memory. Therefore, anundo function can be executed even when the nonvolatile memory forbackup has a small capacity.

The Eighth Embodiment

Each recording apparatus relating to from the first to seventhembodiments records a moving image stream in the MPEG-PS format, to theDVD being a recording medium. As opposed to this, the eighth embodimentrelates to improvement in recording a moving image stream into arecording medium, in accordance with the MPEG2-TS (transport stream)format. In the eighth embodiment, the recording medium that is the usedin recording a moving image stream is BD-RE. FIG. 35 shows the datastructure of a moving image stream to be recorded in a BD-RE, in thesame notation system used for FIG. 3.

AVClip (in the drawing, AVClip#1, #2, and #3) is a moving image streamin the format of MPEG2-TS, which is an alternative for VOB. The AVClipis comprised of a plurality of access units. Each access unit contains aGOP. Since each access unit contains a GOP therein, it becomes possibleto make random access to any beginning of each access unit. Because themoving image stream is recorded in the MPEG2-TS format, the recordingapparatus has to, in playback, first convert the moving image streaminto MPEG-PS format, before supplying to the audio decoder 6 and to thevideo decoder 7.

PlayItem (in the drawing, PlayItem#1, #2, and #3) is information that isan alternative for Cell, and specifies starting/ending points ofplayback sections, with reference to time information.

EP_map (in the drawing, EP_map #1, #2, and #3) is information that is analternative for time map, and shows the playback start time of eachaccess unit in association with the address. The playback start time ofan access unit is represented as a timestamp (presentation timestamp)for the picture data positioning at the beginning of the access unit. Inaddition, the address of an access unit is represented as the serialnumber of the PES packet (SPN (serial packet number).

It can be understood that, also with the moving image stream in MPEG2-TSformat, it is possible to define a playback path comprised of one ormore playback sections. This inevitably results in generation ofnon-referenced part, just as in the first embodiment.

FIG. 36 is a diagram showing the non-referenced parts resulting in theexample of FIG. 35. If such non-referenced parts are generated, thenon-referenced part extraction unit 17 extracts the non-referencedparts, in the same procedures as in the first embodiment, therebydisplaying the parts to the user to prompt the deletion thereof.

As described above, according to the present embodiment, it becomespossible to display the non-referenced parts of the moving image streamwritten into the recording medium even in the MPEG2-TS format, therebyprompting deleting thereof to the user. Therefore, even with recordingapparatuses that can be used in digital broadcast, it becomes possibleto produce the same effect as in the first to seventh embodiments.

The Ninth Embodiment

The ninth embodiment is improved version of the eighth embodiment.Specifically, the improved made in the ninth embodiment is to take intoaccount the increase in size incident to the bridge part, in calculationof the virtual free area.

The bridge part is comprised of a copy part of the rear-end of thepreceding playback section, and a copy part of the front-end of thesucceeding playback section, and is re-encoded so as to yield seamlessconnection. FIG. 37 is a diagram showing the bridge parts created forthe moving image stream of FIG. 36. In this diagram, the following arerecorded in a BD-RE: a bridge part of playback section (1)-playbacksection (2); a bridge part of playback section (2)-playback section (3);and a bridge part of playback section (4)-playback section (5). Here,each set of rear-end/front-end is defined as follows. That is, from theaccess unit including the Out-point of the preceding playback sectionamong the preceding VOB#x to the second access unit are defined as therear-end. And the access unit including the In-point of the succeedingplayback section, among the succeeding VOB#x+1, is defined as thefront-end. The reason for defining the front-end and the rear-end insuch a way is shown in the prior art U.S. Pat. No. 6,148,140 applied bythe same applicant as the present application. Therefore please refer tothis reference for the details.

There will be increase in size as a result of such a bridge part.Therefore in the ninth embodiment, the value obtained by subtracting thesize of the bridge part from the size of the non-referenced part isdisplayed to the user.

-   -   i.e. (data size of non-referenced part)−(size of bridge part)

The value resulting from the above calculation is displayed as a virtualfree area size.

As described above, according to the present embodiment, the virtualfree area that takes into account the size increase incident to thebridge part is displayed to the user. This will enhance the accuracy ofthe virtual free area size.

Seamless connection information is desirably set in the bridge partcreated for seamless connection. The seamless connection information isinformation including: playback start time of the first video frame,playback end time of the last video frame, start time of audio gap, timelength of audio gap, and position information of audio gap. If thisseamless connection information is defined, the difference in timestamps respectively for the two sections (namely, “STC-Offset”) can becalculated from the playback start time of the first video frame, andthe playback end time of the last video frame, and the calculatedSTC-Offset can be set in the playback apparatus. In addition, if audiodecoder control is realized by referring to information on audio gap,interruption of audio incident to playback from one section to anothercan be prevented.

A bridge part may also be provided, with respect to the VOB recorded inthe DVD-Video recording standard. FIG. 37 is a diagram showing thebridge part generated for the VOB of FIG. 4. Also in the first toseventh embodiments, it is possible to calculate a more accurate virtualfree area size, if these embodiments take into account the size increasedue to the bridge part in calculation of the virtual free area size.

The Tenth Embodiment

From the first to ninth embodiments, the part not referenced by thePlayList is extracted as non-referenced part. However in this tenthembodiment, from among a moving image stream, the part that a userplayed back for more than twice is to be specified in the PlayList.Then, the parts resulting from subtracting the part specified in thePlayList from the entire moving image stream is extracted asnon-referenced parts.

That is, the part that the user played back for more than twice isconsidered having high preservation value. In the tenth embodiment, sucha part is specified in the PlayList. On the other hand, parts eitherplayed back once, or not played back at all have a great possibility ofbeing deleted in the future. Therefore the tenth embodiment extractssuch parts as non-referenced part.

Such an extraction will leave only necessary parts in the recordingmedium, among the moving image streams in the user's stock. This willfacilitate cleanup of non-referenced part.

Note that “twice” used here is one example, and the standard occurrencemay be third times, fourth times, for example.

Supplementary Note for the First to Tenth Embodiments

So far, the present invention has been described by way of embodiments.However, these embodiments are only system examples that are expected tohave the best possible effects in the present state of the art. Needlessto say, the present invention may be realized with changes andmodification, which are not depart from the essence of the invention.The representative examples of such changes and modifications includethe following (A), (B), (C) . . . .

(A) The recording apparatus of each embodiment is used by beingconnected to the television 101. However, the recording apparatus may beintegrated into a liquid crystal display, and the like. The recordingapparatus may alternatively be included in such as a digital televisionthat includes a recording medium therein. In addition, the recordingapparatus of the first embodiment includes therein a DVD drive 1 and anMPEG decoder 4. However, this recording apparatus may be connected tothese DVD drive 1-MPEG decoder 4, via an IEEE1394 connector, instead ofincluding the mentioned units therein. Furthermore, in the recordingapparatus in each embodiment, only the system LSI that is the essentialpart for performing the processes can be considered a recordingapparatus.

Since these recording apparatuses each are an invention described in thedescription, the act of producing such recording apparatuses having theinternal structure of the recording apparatuses of the embodiments is anact of implementing the invention described in the presentspecification. In addition, any act of transferring either with orwithout charge (i.e. for sale or as a gift), renting, or importing,constitutes an act of implementing the present invention. Any act ofoffering the mentioned transferring, renting and the like, to users ingeneral, such as by exhibition at the shop, through cataloguesolicitation, and by distribution of pamphlets, also constitutes an actof implementing the recording apparatus in this invention. (B) Theinformation processing by way of the programs shown in FIGS. 12, 13, 14,21, 22, 24, 26, 28, 30, 31, and 32 is concretely realized using thehardware resources such as a CPU, an MPEG decoder, and a DVD drive.Specifically, the recording apparatuses of the first to seventhembodiments are constructed as a result of the information processingfor the purpose of deleting non-referenced part, which is performed by aconcrete means that is realized by cooperation between the programs andthe hardware.

Since the information processing by way of a program is concretelyrealized with use of the hardware resource, the programs whose processesare shown in FIGS. 12-32 are considered creation of technical idea usinga rule of nature, and so each program, by itself, can be considered aseparate invention. Since each program itself is an invention, theprogram is considered a specified invention, and each recordingapparatus relating to the present invention is considered a productinvention whose main part is the corresponding program being thespecified invention.

In each embodiment, the program described is to be used as the main partof the recording apparatus relating to the present invention. However,since the program itself is an invention, the program can be implementedin the state of being separated from the recording apparatus. The act ofimplementing each program by itself includes: (1) act of producing theprogram, (2) act of transferring the program with or without charge, (3)act of renting, (4) act of importing, (5) act of providing the generalpublic with the program via an interactive electric communicationcircuit, and (6) act of offering transfer or renting of the program, tousers in general, such as by exhibition at the shop, through cataloguesolicitation, and by distribution of pamphlets.

The categories of the aforementioned (2) transferring act and (3)renting act include an act of distributing, in the market, the programrecorded in a recording medium, and an act of providing the generalpublic with the program via the one-way broadcast network.

The category of (5) providing act via an interactive electriccommunication circuit includes: a case that a provider sends the programto a user, for allowing the user to use the program (program downloadservice); and an act of providing only the function of the program viaan electric communication circuit for allowing the user to use thefunction, while keeping the program itself at the hand of the provider(function-providing type ASP service).

(C) In the flowcharts of FIGS. 12, 13, 14, 21, 22, 24, 26, 28, 30, 31,and 32, the time concept, which each step executed chronologically has,is supposed to be an indispensable item for specifying the presentinvention. By chronologically executing the process of each step in theflowcharts, deletion of non-referenced part, which is the originalpurpose of the invention, and further the production of certain actionand effect relating thereto, are realized. Therefore, the methodsdescribed in the flowcharts of FIGS. 12-32 are considered creation oftechnical idea using a rule of nature, and each of the methods isconsidered as an invention by itself. Accordingly, if the processes ofthese flowcharts are executed, so as to delete non-referenced part,which is the original purpose of the invention, thereby producingcertain action and effect, this act corresponds to an act ofimplementing the recording method relating to the present invention.

(D) In the description flow of each embodiment, the recording medium inwhich contents are recorded is considered a DVD. However, the physicalnature of this DVD does not contribute to the exertion of action andeffect of the present invention so much. In view of this, otherrecording media having a capacity to record contents can be equally usedin place of DVD. Needless to say, the representative of the recordingmedia are optical disks other than DVD, such as CD-R, CD-RW, Blue-rayDisc. Alternatively, optical magnetic disks such as PD, and MO may beused. Furthermore, semiconductor memory cards such as a SD memory card,a compact flash card, smart media, a memory stick, a multimedia card,and a PCM-CIA card may be equally used. Moreover, magnetic recordingdisks such as SuperDisk, Zip, and Clik!, and removable hard disk drivessuch as ORB, Jaz, SparQ, SyJet, EZFley, and a microdrive may be equallyused too.

(E) The contents in the embodiments may be obtained by encodinganalogue/digital video signals recorded in videotape. Alternatively, thecontents may be obtained by encoding analogue/digital video signalsdirectly taken into from a video camera. In addition, the contents maybe digital work such as movie distributed in the state prestored in arecording medium, and digital work distributed by a distribution server.

In addition, the content in each embodiment may be one unit of broadcastprogram defined by a broadcast station.

(F) In the first embodiment, the VOBU including In-point and the VOBUincluding Out-point are re-encoded. However, it is still effective,without performing the mentioned re-encoding, to only delete VOBUspositioning between the In-point-including VOBU and theOut-point-including VOBU. In such a case, care should be taken to leave,in the DVD, the VOBUs that are to be played back in synchronization withthe picture data within the Out-point including VOBU, and the VOBUs thathave dependency relation with the picture data within the In-pointincluding VOBU, and only to delete other VOBUs. If the VOBUs mentionedto be left in the DVD are deleted, it is possible to have interruptionin playback of picture data or in audio.

(G) In the non-referenced part navigators, thumbnails are displayed thatrelate to the In-point and the Out-point of a non-referenced part.Alternatively, however, picture data positioning midway through anon-referenced part may be displayed as a thumbnail.

In addition, a plurality of pieces of picture data may be selected froma non-referenced part in a predetermined time interval, and a pluralityof thumbnails corresponding thereto may be displayed in a non-referencedpart navigator. The user will be able to recall the contents of thenon-referenced part more clearly, by this construction of displaying aplurality of thumbnails in a non-referenced part navigator.

(H) In each embodiment, a video stream and an audio stream aremultiplexed into a VOB. However, other information may be alsomultiplexed thereto, the other information including sub-picture streamin which characters of subtitles are compressed in run-length method,and other control information. In addition, the MPEG encoder 3 and MPEGdecoder 4 are a codec in MPEG2 image decoding/decompressing method, butmay alternatively be other decoding codecs in imagedecoding/decompressing method that are different from MPEG2, such asMPEG1 and MPEG4.

(I) In the first to seventh embodiments, the selection operation forPG/PL performed by a user is received via a remote controller. However,specification by a user may be received via a front panel of a playbackapparatus, too. Alternatively, specification by a user may be receivedvia input apparatuses such as a keyboard, a touch panel, a mouse and apad, and a track ball. In this case, the user specification may bereceived through such as a click operation and a drug operation.

INDUSTRIAL APPLICABILITY

A recording apparatus relating to the present invention attempts tomaintain free area in a recording medium, while making use of merits ofplaylist editing. The recording apparatus thereby heightens commercialvalue of a DVD recorder, an HD recorder, and the like, and so helpsintroducing attractive goods in the market. The recording apparatustherefore has a possibility of being of great use in the consumer goodsindustry.

1. A recording apparatus that writes a video stream to a recordingmedium and edits the video stream, the recording apparatus comprising:an editing unit operable to specify, in accordance with a useroperation, a plurality of parts of the video stream as playbacksections; a display unit operable to display to the user, a plurality ofparts that remain after the playback sections are subtracted from thevideo stream, as non-referenced parts; and a deletion unit operable todelete at least one of the displayed non-referenced parts from therecording medium, according to a user operation.
 2. The recordingapparatus of claim 1, wherein each of the playback sections isrepresented by a set of starting/ending positions of a playbackoperation, and the plurality of non-referenced parts include a part froma front-end of the video stream to immediately before a startingposition of one of the playback sections that appears first, and a partfrom immediately after an ending position of one of the playbacksections that appears last to a rear-end of the video stream.
 3. Therecording apparatus of claim 2, wherein the non-referenced parts includeevery part immediately after one of the playback sections to immediatelybefore another of the playback sections that follows.
 4. The recordingapparatus of claim 1, wherein the display performed by the display unitis one of: sequential playback of a plurality of pieces of picture dataincluded in the non-referenced parts; and disposing, on a screen, of aplurality of thumbnails each corresponding to the pieces of picturedata.
 5. The recording apparatus of claim 1, wherein a plurality ofvideo streams are written to the recording medium, each stream beingclassified into two or more contents, and the deletion unit deletes onlynon-referenced parts included in a certain content.
 6. The recordingapparatus of claim 5, further comprising: a list-display unit operableto display a list of the contents in the recording medium; and areception unit operable to receive, from the user, specification of thecertain content whose non-referenced parts are to be deleted, whereinthe non-referenced parts deleted by the deletion unit are included inthe certain content whose specification has been received by thereception unit.
 7. The recording apparatus of claim 6, wherein a numberof contents whose specification is to be received by the reception unitis two or more.
 8. The recording apparatus of claim 1, furthercomprising: a reception unit operable to receive, from the user, anoperation for programming a recording; and a calculation unit operableto calculate an area size required for the programmed recording, whereinthe display unit performs the display, only if the calculated area sizeexceeds a free area size of the recording medium, and the display unitfurther displays a message making an inquiry to the user about whetherthe non-referenced parts should be deleted.
 9. The recording apparatusof claim 1, further comprising: a reception unit operable to receive,from the user, specification of an environment setting value, theenvironment setting value being a minimum free area size that therecording medium should allocate, wherein the display unit performs thedisplay, only if the calculated area size exceeds a free area size ofthe recording medium, and the display unit further displays a messagemaking an inquiry to the user about whether the non-referenced partsshould be deleted.
 10. The recording apparatus of claim 1, furthercomprising: a backup unit operable to record therein a backup of thenon-referenced parts, prior to the deletion performed by the deletionunit; an inquiry unit operable, after the deletion performed by thedeletion unit, to make an inquiry to the user about whether an undooperation should be performed; and a write back unit operable, if theuser's answer to the inquiry is affirmative, to write back the backuprecorded in the backup unit to the recording medium.
 11. Acomputer-readable program that makes a computer write a video stream toa recording medium and edit the video stream, the program making acomputer perform a procedure comprising: an editing step of specifying,in accordance with a user operation, a plurality of parts of the videostream as playback sections; a display step of displaying to the user, aplurality of parts that remain after the playback sections aresubtracted from the video stream, as non-referenced parts; and adeletion step of deleting at least one of the displayed non-referencedparts from the recording medium, according to a user operation.
 12. Theprogram of claim 11, wherein each of the playback sections isrepresented by a set of starting/ending positions of a playbackoperation, and the plurality of non-referenced parts include a part froma front-end of the video stream to immediately before a startingposition of one of the playback sections that appears first, and a partfrom immediately after an ending position of one of the playbacksections that appears last to a rear-end of the video stream.
 13. Theprogram of claim 12, wherein the non-referenced parts include every partimmediately after one of the playback sections to immediately beforeanother of the playback sections that follows.
 14. The program of claim11, wherein the display performed at the display step is one of:sequential playback of a plurality of pieces of picture data included inthe non-referenced parts; and disposing, on a screen, of a plurality ofthumbnails each corresponding to the pieces of picture data.
 15. Theprogram of claim 11, wherein a plurality of video streams are written tothe recording medium, each stream being classified into two or morecontents, and at the deletion step, only non-referenced parts includedin a certain content are deleted.
 16. The program of claim 15, whereinthe procedure further comprises: a list-display step of displaying alist of the contents in the recording medium; and a reception step ofreceiving, from the user, specification of the certain content whosenon-referenced parts are to be deleted, where the non-referenced partsdeleted at the deletion step are included in the certain content whosespecification has been received at the reception step.
 17. The programof claim 16, wherein a number of contents whose specification is to bereceived at the reception step is two or more.
 18. The program of claim11, wherein the procedure further comprises: a reception step ofreceiving, from the user, an operation for programming a recording; anda calculation step of calculating an area size required for theprogrammed recording, where at the display step, the display isperformed only if the calculated area size exceeds a free area size ofthe recording medium, and at the display step, a message making aninquiry to the user about whether the non-referenced parts should bedeleted is further displayed.
 19. The program of claim 11, wherein theprocedure further comprises: a reception step of receiving, from theuser, specification of an environment setting value, the environmentsetting value being a minimum free area size that the recording mediumshould allocate, where at the display step, the display is performedonly if the calculated area size exceeds a free area size of therecording medium, and at the display step, a message making an inquiryto the user about whether the non-referenced parts should be deleted isfurther displayed.
 20. The program of claim 11, wherein the procedurefurther comprises: a backup step of recording therein a backup of thenon-referenced parts, prior to the deletion performed at the deletionstep; an inquiry step of, after the deletion performed at the deletionstep, making an inquiry to the user about whether an undo operationshould be performed; and a write back step of, if the user's answer tothe inquiry is affirmative, writing back the backup recorded in thebackup unit to the recording medium.
 21. A system LSI that performscontrol with respect to a drive device for a recording medium, therecording medium storing therein at least one video stream, the systemLSI comprising: an editing unit operable to specify, in accordance witha user operation, a plurality of parts of the video stream as playbacksections; a display unit operable to display to the user, a plurality ofparts that remain after the playback sections are subtracted from thevideo stream, as non-referenced parts; and a deletion unit operable todelete at least one of the displayed non-referenced parts from therecording medium, according to a user operation.
 22. The system LSI ofclaim 21, wherein each of the playback sections is represented by a setof starting/ending positions of a playback operation, and the pluralityof non-referenced parts include a part from a front-end of the videostream to immediately before a starting position of one of the playbacksections that appears first, and a part from immediately after an endingposition of one of the playback sections that appears last to a rear-endof the video stream.
 23. The system LSI of claim 22, wherein thenon-referenced parts include every part immediately after one of theplayback sections to immediately before another of the playback sectionsthat follows.
 24. The system LSI of claim 21, wherein the displayperformed by the display unit is one of: sequential playback of aplurality of pieces of picture data included in the non-referencedparts; and disposing, on a screen, of a plurality of thumbnails eachcorresponding to the pieces of picture data.
 25. The system LSI of claim21, wherein a plurality of video streams are written to the recordingmedium, each stream being classified into two or more contents, and thedeletion unit deletes only non-referenced parts included in a certaincontent.
 26. The system LSI of claim 25, further comprising: alist-display unit operable to display a list of the contents in therecording medium; and a reception unit operable to receive, from theuser, specification of the certain content whose non-referenced partsare to be deleted, wherein the non-referenced parts deleted by thedeletion unit are included in the certain content whose specificationhas been received by the reception unit.
 27. The system LSI of claim 26,a number of contents whose specification is to be received by thereception unit is two or more.
 28. The system LSI of claim 21, furthercomprising: a reception unit operable to receive, from the user, anoperation for programming a recording; and a calculation unit operableto calculate an area size required for the programmed recording, whereinthe display unit performs the display, only if the calculated area sizeexceeds a free area size of the recording medium, and the display unitfurther displays a message making an inquiry to the user about whetherthe non-referenced parts should be deleted.
 29. The system LSI of claim21, further comprising: a reception unit operable to receive, from theuser, specification of an environment setting value, the environmentsetting value being a minimum free area size that the recording mediumshould allocate, wherein the display unit performs the display, only ifthe calculated area size exceeds a free area size of the recordingmedium, and the display unit further displays a message making aninquiry to the user about whether the non-referenced parts should bedeleted.
 30. The system LSI of claim 21, further comprising: a backupunit operable to record therein a backup of the non-referenced parts,prior to the deletion performed by the deletion unit; an inquiry unitoperable, after the deletion performed by the deletion unit, to make aninquiry to the user about whether an undo operation should be performed;and a write back unit operable, if the user's answer to the inquiry isaffirmative, to write back the backup recorded in the backup unit to therecording medium.